Planes

When characters reach higher levels, their grasp extends to other dimensions of reality—or, as we call them, planes of existence. The PCs may rescue a friend from the evil depths of the Abyss, or sail the shining waters of the River Oceanus. They might hoist a tankard with the friendly giants of Ysgard, or face the chaos of Limbo to reach a wizened githzerai sage.

The planes of existence in the D&D game world make up the D&D cosmology, which is the topic of this section. These planes are strange and usually dangerous environments; the strangest of them are as unlike the so-called “real world” as any place can be. While planar adventures can be dangerous, they can be wondrous as well. The characters might visit a plane composed entirely of solid fire, or test their mettle on a battlefield where the fallen are resurrected with each dawn.

Because the spells required to reach other planes are all 6th level and higher, planar adventures are almost exclusively the province of high-level PCs. Not only are the other planes full of powerful outsiders and elementals, but the planes themselves have deadly environments that only well-prepared adventurers can withstand.

The D&D cosmology has twenty-seven different planes of existence, offering everything from the normality of the Material Plane (the real world) to the serenity of the Astral Plane to the pervasive evil of the Nine Hells. This section details the traits and characteristics that certain planes have in common and features a short description of each plane that includes a possible adventure site.

What is a Plane?

The planes of existence are different realities with interwoven connections. Except for rare linking points, each plane is effectively its own universe with its own natural laws.

The planes break down into a number of general types: the Material Plane, the Transitive Planes, the Inner Planes, the Outer Planes, and the demiplanes.

Material Plane: The Material Plane tends to be the most Earthlike of all planes and operates under the same set of natural laws that our own real world does. This is the default plane for most adventures.

Transitive Planes: These three planes have one important common characteristic: Each is used to get from one place to another. The Astral Plane is a conduit to all other planes, while the Ethereal Plane and the Plane of Shadow both serve as means of transportation within the Material Plane they’re connected to. These planes have the strongest regular interaction with the Material Plane and are often accessed by using various spells. They have native inhabitants as well.

Inner Planes: These six planes are manifestations of the basic building blocks of the universe. Each is made up of a single type of energy or element that overwhelms all others. The natives of a particular Inner Plane are made of the same energy or element as the plane itself.

Outer Planes: The deities live on the Outer Planes, as do creatures such as celestials, demons, and devils. Each of the Outer Planes has an alignment, representing a particular moral or ethical outlook, and the natives of each plane tend to behave in agreement with that plane’s alignment. The Outer Planes are also the final resting place of souls from the Material Plane, whether that final rest takes the form of calm introspection or eternal damnation.

Demiplanes: This catch-all category covers all extradimensional spaces that function like planes but have measurable size and limited access. Other kinds of planes are theoretically infinite in size, but a demiplane might be only a few hundred feet across. Access to demiplanes may be limited to particular locations (such as a fixed gateway) or particular situations (such as a time of year or a weather condition). Some demiplanes are created by powerful magic, some naturally evolve, and some appear according to the will of the deities.

In the D&D cosmology, also known as the Great Wheel, the planes are connected in a specific fashion, as depicted here. (The description does not include demiplanes, because the location and even the existence of these extradimensional spaces is constantly changing.)

Planar Traits

Each plane of existence has its own properties⁠—the natural laws of its universe.

Planar traits are broken down into a number of general areas. All planes have the following kinds of traits.

Physical Traits: These traits determine the laws of physics and nature on the plane, including how gravity and time function.

Elemental and Energy Traits: These traits determine the dominance of particular elemental or energy forces.

Alignment Traits: Just as characters may be lawful neutral or chaotic good, many planes are tied to a particular moral or ethical outlook.

Magic Traits: Magic works differently from plane to plane, and magic traits set the boundaries for what it can and can’t do.

Physical Traits

The two most important natural laws set by physical traits are how gravity works and how time passes. Other physical traits pertain to the size and shape of a plane and how easily a plane’s nature can be altered.

Gravity: The direction of gravity’s pull may be unusual, and it might even change directions within the plane itself.

Normal Gravity: Most planes have gravity similar to that of the Material Plane. The usual rules for ability scores, carrying capacity, and encumbrance apply. Unless otherwise noted in a description, it is assumed every plane has the normal gravity trait.

Heavy Gravity: The gravity on a plane with this trait is much more intense than on the Material Plane. As a result, Balance, Climb, Jump, Ride, Swim, and Tumble checks incur a –⁠2 circumstance penalty, as do all attack rolls. All item weights are effectively doubled, which might affect a character’s speed. Weapon ranges are halved. A character’s Strength and Dexterity scores are not affected. Characters who fall on a heavy gravity plane take 1d10 points of damage for each 10 feet fallen, to a maximum of 20d10 points of damage.

Light Gravity: The gravity on a plane with this trait is less intense than on the Material Plane. As a result, creatures find that they can lift more, but their movements tend to be ungainly. Characters on a plane with the light gravity trait take a –⁠2 circumstance penalty on attack rolls and Balance, Ride, Swim, and Tumble checks. All items weigh half as much. Weapon ranges double, and characters gain a +2 circumstance bonus on Climb and Jump checks. Strength and Dexterity don’t change as a result of light gravity, but what you can do with such scores does change. These advantages apply to travelers from other planes as well as natives.

Falling characters on a light gravity plane take 1d4 points of damage for each 10 feet of the fall (maximum 20d4).

No Gravity: Individuals on a plane with this trait merely float in space, unless other resources are available to provide a direction for gravity’s pull.

Objective Directional Gravity: The strength of gravity on a plane with this trait is the same as on the Material Plane, but the direction is not the traditional “down” toward the ground. It may be down toward any solid object, at an angle to the surface of the plane itself, or even upward.

In addition, objective directional gravity may change from place to place. The direction of “down” may vary.

Subjective Directional Gravity: The strength of gravity on a plane with this trait is the same as on the Material Plane, but each individual chooses the direction of gravity’s pull. Such a plane has no gravity for unattended objects and nonsentient creatures. This sort of environment can be very disorienting to the newcomer, but is common on “weightless” planes.

Characters on a plane with subjective directional gravity can move normally along a solid surface by imagining “down” near their feet. If suspended in midair, a character “flies” by merely choosing a “down” direction and “falling” that way. Under such a procedure, an individual “falls” 150 feet in the first round and 300 feet in each succeeding round. Movement is straight-line only. In order to stop, one has to slow one’s movement by changing the designated “down” direction (again, moving 150 feet in the new direction in the first round and 300 feet per round thereafter).

It takes a DC 16 Wisdom check to set a new direction of gravity as a free action; this check can be made once per round. Any character who fails this Wisdom check in successive rounds receives a +6 bonus on subsequent checks until he or she succeeds.

Time: The rate of time’s passage can vary on different planes, though it remains constant within any particular plane. Time is always subjective for the viewer. The same subjectivity applies to various planes. Travelers may discover that they’ll pick up or lose time while moving among the planes, but from their point of view, time always passes naturally.

Normal Time: This trait describes the way time passes on the Material Plane. One hour on a plane with normal time equals one hour on the Material Plane. Unless otherwise noted in a description, every plane has the normal time trait.

Timeless: On planes with this trait, time still passes, but the effects of time are diminished. How the timeless trait can affect certain activities or conditions such as hunger, thirst, aging, the effects of poison, and healing varies from plane to plane.

The danger of a timeless plane is that once one leaves such a plane for one where time flows normally, conditions such as hunger and aging do occur retroactively.

Flowing Time: On some planes, time can flow faster or slower. One may travel to another plane, spend a year there, then return to the Material Plane to find that only six seconds have elapsed. Everything on the plane returned to is only a few seconds older. But for that traveler and the items, spells, and effects working on him, that year away was entirely real.

When designating how time works on planes with flowing time, put the Material Plane’s flow of time first, followed by the same flow in the other plane.

Erratic Time: Some planes have time that slows down and speeds up, so an individual may lose or gain time as he moves between the two planes. The following is provided as an example.

To the denizens of such a plane, time flows naturally and the shift is unnoticed.

If a plane is timeless with respect to magic, any spell cast with a noninstantaneous duration is permanent until dispelled.

Shape and Size: Planes come in a variety of sizes and shapes. Most planes are infinite, or at least so large that they may as well be infinite.

Infinite: Planes with this trait go on forever, though they may have finite components within them. Or they may consist of ongoing expanses in two directions, like a map that stretches out infinitely.

Finite Shape: A plane with this trait has defined edges or borders. These borders may adjoin other planes or hard, finite borders such as the edge of the world or a great wall. Demiplanes are often finite.

Self-Contained Shape: On planes with this trait, the borders wrap in on themselves, depositing the traveler on the other side of the map. A spherical plane is an example of a self-contained, finite plane, but there can be cubes, toruses, and flat planes with magical edges that teleport the traveler to an opposite edge when he crosses them.

Some demiplanes are self-contained.

Morphic Traits: This trait measures how easily the basic nature of a plane can be changed. Some planes are responsive to sentient thought, while others can be manipulated only by extremely powerful creatures. And some planes respond to physical or magical efforts.

Alterable Morphic: On a plane with this trait, objects remain where they are (and what they are) unless affected by physical force or magic. You can change the immediate environment as a result of tangible effort.

Highly Morphic: On a plane with this trait, features of the plane change so frequently that it’s difficult to keep a particular area stable. Such planes may react dramatically to specific spells, sentient thought, or the force of will. Others change for no reason.

Magically Morphic: Specific spells can alter the basic material of a plane with this trait.

Divinely Morphic: Specific unique beings (deities or similar great powers) have the ability to alter objects, creatures, and the landscape on planes with this trait. Ordinary characters find these planes similar to alterable planes in that they may be affected by spells and physical effort. But the deities may cause these areas to change instantly and dramatically, creating great kingdoms for themselves.

Static: These planes are unchanging. Visitors cannot affect living residents of the plane, nor objects that the denizens possess. Any spells that would affect those on the plane have no effect unless the plane’s static trait is somehow removed or suppressed. Spells cast before entering a plane with the static trait remain in effect, however.

Even moving an unattended object within a static plane requires a DC 16 Strength check. Particularly heavy objects may be impossible to move.

Sentient: These planes are ones that respond to a single thought⁠—that of the plane itself. Travelers would find the plane’s landscape changing as a result of what the plane thought of the travelers, either becoming more or less hospitable depending on its reaction.

Elemental and Energy Traits

Four basic elements and two types of energy together make up everything. The elements are earth, air, fire, and water. The types of energy are positive and negative.

The Material Plane reflects a balancing of those elements and energies; all are found there. Each of the Inner Planes is dominated by one element or type of energy. Other planes may show off various aspects of these elemental traits. Many planes have no elemental or energy traits; these traits are noted in a plane’s description only when they are present.

Air-Dominant: Mostly open space, planes with this trait have just a few bits of floating stone or other elements. They usually have a breathable atmosphere, though such a plane may include clouds of acidic or toxic gas. Creatures of the earth subtype are uncomfortable on air-dominant planes because they have little or no natural earth to connect with. They take no actual damage, however.

Earth-Dominant: Planes with this trait are mostly solid. Travelers who arrive run the risk of suffocation if they don’t reach a cavern or other pocket within the earth. Worse yet, individuals without the ability to burrow are entombed in the earth and must dig their way out (5 feet per turn). Creatures of the air subtype are uncomfortable on earth dominant planes because these planes are tight and claustrophobic to them. But they suffer no inconvenience beyond having difficulty moving.

Fire-Dominant: Planes with this trait are composed of flames that continually burn without consuming their fuel source. Fire-dominant planes are extremely hostile to Material Plane creatures, and those without resistance or immunity to fire are soon immolated.

Unprotected wood, paper, cloth, and other flammable materials catch fire almost immediately, and those wearing unprotected flammable clothing catch on fire. In addition, individuals take 3d10 points of fire damage every round they are on a fire-dominant plane. Creatures of the water subtype are extremely uncomfortable on fire-dominant planes. Those that are made of water take double damage each round.

Water-Dominant: Planes with this trait are mostly liquid. Visitors who can’t breathe water or reach a pocket of air will likely drown. Creatures of the fire subtype are extremely uncomfortable on water-dominant planes. Those made of fire take 1d10 points of damage each round.

Positive-Dominant: An abundance of life characterizes planes with this trait. The two kinds of positive-dominant traits are minor positive-dominant and major positive-dominant. A minor positive-dominant plane is a riotous explosion of life in all its forms. Colors are brighter, fires are hotter, noises are louder, and sensations are more intense as a result of the positive energy swirling through the plane. All individuals in a positive-dominant plane gain fast healing 2 as an extraordinary ability.

Major positive-dominant planes go even further. A creature on a major positive-dominant plane must make a DC 15 Fortitude save to avoid being blinded for 10 rounds by the brilliance of the surroundings. Simply being on the plane grants fast healing 5 as an extraordinary ability. In addition, those at full hit points gain 5 additional temporary hit points per round. These temporary hit points fade 1d20 rounds after the creature leaves the major positive-dominant plane. However, a creature must make a DC 20 Fortitude save each round that its temporary hit points exceed its normal hit point total. Failing the saving throw results in the creature exploding in a riot of energy, killing it.

Negative-Dominant: Planes with this trait are vast, empty reaches that suck the life out of travelers who cross them. They tend to be lonely, haunted planes, drained of color and filled with winds bearing the soft moans of those who died within them. As with positive-dominant planes, negative-dominant planes can be either minor or major. On minor negative-dominant planes, living creatures take 1d6 points of damage per round. At 0 hit points or lower, they crumble into ash.

Major negative-dominant planes are even more severe. Each round, those within must make a DC 25 Fortitude save or gain a negative level. A creature whose negative levels equal its current levels or Hit Dice is slain, becoming a wraith. The death ward spell protects a traveler from the damage and energy drain of a negative-dominant plane.

Alignment Traits

Some planes have a predisposition to a certain alignment. Most of the inhabitants of these planes also have the plane’s particular alignment, even powerful creatures such as deities. In addition, creatures of alignments contrary to the plane have a tougher time dealing with its natives and situations.

The alignment trait of a plane affects social interactions there. Characters who follow other alignments than most of the inhabitants do may find life more difficult.

Alignment traits have multiple components. First are the moral (good or evil) and ethical (lawful or chaotic) components; a plane can have either a moral component, an ethical component, or one of each. Second, the specific alignment trait indicates whether each moral or ethical component is mildly or strongly evident.

Good-Aligned/Evil-Aligned: These planes have chosen a side in the battle of good versus evil. No plane can be both good-aligned and evil-aligned.

Law-Aligned/Chaos-Aligned: Law versus chaos is the key struggle for these planes and their residents. No plane can be both law-aligned and chaos-aligned.

Each part of the moral/ethical alignment trait has a descriptor, either “mildly” or “strongly,” to show how powerful the influence of alignment is on the plane.

Mildly Aligned: Creatures who have an alignment opposite that of a mildly aligned plane take a –⁠2 circumstance penalty on all Charisma-based checks.

Strongly Aligned: On planes that are strongly aligned, a –⁠2 circumstance penalty applies on all Charisma-based checks made by all creatures not of the plane’s alignment. In addition, the –⁠2 penalty affects all Intelligence-based and Wisdom-based checks, too.

The penalties for the moral and ethical components of the alignment trait do stack.

Neutral-Aligned: A mildly neutral-aligned plane does not apply a circumstance penalty to anyone.

The Material Plane is considered mildly neutral-aligned, though it may contain high concentrations of evil or good, law or chaos in places.

A strongly neutral-aligned plane would stand in opposition to all other moral and ethical principles: good, evil, law, and chaos. Such a plane may be more concerned with the balance of the alignments than with accommodating and accepting alternate points of view. In the same fashion as for other strongly aligned planes, strongly neutral-aligned planes apply a –⁠2 circumstance penalty to Intelligence-, Wisdom-, or Charisma-based checks by any creature that isn’t neutral. The penalty is applied twice (once for law/chaos, and once for good/evil), so neutral good, neutral evil, lawful neutral, and chaotic neutral creatures take a –⁠2 penalty and lawful good, chaotic good, chaotic evil, and lawful evil creatures take a –⁠4 penalty.

Magic Traits

A plane’s magic trait describes how magic works on the plane compared to how it works on the Material Plane. Particular locations on a plane (such as those under the direct control of deities) may be pockets where a different magic trait applies.

Normal Magic: This magic trait means that all spells and supernatural abilities function as written. Unless otherwise noted in a description, every plane has the normal magic trait.

Wild Magic: On a plane with the wild magic trait spells and spell-like abilities function in radically different and sometimes dangerous ways. Any spell or spell-like ability used on a wild magic plane has a chance to go awry. The caster must make a level check (DC 15 + the level of the spell or effect) for the magic to function normally. For spell-like abilities, use the level or HD of the creature employing the ability for the caster level check and the level of the spell-like ability to set the DC for the caster level check. Failure on this check means that something strange happens; roll d% and consult the following table.

Impeded Magic: Particular spells and spell-like abilities are more difficult to cast on planes with this trait, often because the nature of the plane interferes with the spell.

To cast an impeded spell, the caster must make a Spellcraft check (DC 20 + the level of the spell). If the check fails, the spell does not function but is still lost as a prepared spell or spell slot. If the check succeeds, the spell functions normally.

Enhanced Magic: Particular spells and spell-like abilities are easier to use or more powerful in effect on planes with this trait than they are on the Material Plane.

Natives of a plane with the enhanced magic trait are aware of which spells and spell-like abilities are enhanced, but planar travelers may have to discover this on their own.

If a spell is enhanced, certain metamagic feats can be applied to it without changing the spell slot required or the casting time. Spellcasters on the plane are considered to have that feat or feats for the purpose of applying them to that spell. Spellcasters native to the plane must gain the feat or feats normally if they want to use them on other planes as well.

Limited Magic: Planes with this trait permit only the use of spells and spell-like abilities that meet particular qualifications.

Magic can be limited to effects from certain schools or subschools, to effects with certain descriptors, or to effects of a certain level (or any combination of these qualities). Spells and spell-like abilities that don’t meet the qualifications simply don’t work.

Dead Magic: These planes have no magic at all. A plane with the dead magic trait functions in all respects like an antimagic field spell. Divination spells cannot detect subjects within a dead magic plane, nor can a spellcaster use teleport or another spell to move in or out. The only exception to the “no magic” rule is permanent planar portals, which still function normally.

How Planes Interact

By definition, planes are infinite or near-infinite expanses, whether they are flat worlds, layered vaults, or spheres hanging in space. How, then, can they interact with each other?

As a metaphor, imagine the various planes of a cosmology floating near each other in a three-dimensional constellation or cluster. They are not necessarily “above” or “below” each other, though there is a social tendency to call good-aligned planes “upper” planes and evil-aligned planes “lower” planes. What is important to the D&D cosmology is whether two given planes are separate, coterminous, or coexistent.

Separate Planes: Two planes that are separate do not overlap or directly connect to each other. They are like planets in different orbits. Any Outer Plane, for example, has no direct connection with the Material Plane. The two planes are separate, and the only way to get from one plane to the other is to go through a third plane, such as the Astral Plane.

Coterminous Planes: Planes that touch at specific points are coterminous. Where they touch, a connection exists, and travelers can leave one reality behind and enter the other. It’s possible, for example, to sail from Hades to the Abyss on the River Styx.

Coexistent Planes: If a link between two planes can be created at any point, the two planes are coexistent. These planes overlap each other completely. A coexistent plane can be reached from anywhere on the plane it overlaps. When moving on a coexistent plane, it is often possible to see into or interact with the plane it coexists with. The Ethereal Plane is coexistent with the Material Plane, and inhabitants of the Ethereal Plane can see into the Material Plane. With the right magic, inhabitants of the Material Plane can likewise see and interact with those on the Ethereal Plane (see invisibility and magic missile, for example, both affect the Ethereal Plane).

The D&D Cosmology

The D&D cosmology is structured as follows.

The Material Plane is at its center.

The Plane of Shadow and the Ethereal Plane are coexistent with the Material Plane. All planes, including the Plane of Shadow and the Ethereal Plane, are coexistent with the Astral Plane, which envelops the whole cosmology like a cloud.

The six Inner Planes surround the Material Plane. They are separate from the Material Plane and from each other (they do not have connections between them). They are each coexistent with the Astral Plane. Each of the Inner Planes has the appropriate elemental or energy trait.

The Outer Planes are arranged in a great wheel around the Material Plane. Each Outer Plane is coterminous to the planes on either side of it but separate from the other Outer Planes. The exception is the Concordant Domain of the Outlands, which is coterminous to every other Outer Plane and thus serves as a central hub for dealings between outsiders.

The Outer Planes are coexistent with the Astral Plane. They are separate from the Ethereal Plane and the Plane of Shadow, so certain spells (ethereal jaunt, for example) aren’t available to a caster on the Outer Planes. Each Outer Planes is made up of related layers (see Layered Planes, below), and the most common access to an Outer Plane is through the top layer of each plane. The goodaligned planes, also called the celestial planes or the upper planes, are linked by the path of the River Oceanus. The evil-aligned planes, also called the infernal planes or the lower planes, are linked by the path of the River Styx.

A large number of finite demiplanes connect all over the place. Individual conduits, freestanding portals, and vortices are also common.

Layered Planes

Infinities may be broken into smaller infinities, and planes into smaller, related planes. These layers are effectively separate planes of existence, and each layer can have its own planar traits. Layers are connected to each other through a variety of planar gates, natural vortices, paths, and shifting borders.

Access to a layered plane from elsewhere usually happens on a specific layer: the first layer of the plane, which can be either the top layer or the bottom layer, depending on the specific plane. Most fixed access points (such as portals and natural vortices) reach this layer, which makes it the gateway for other layers of the plane. The plane shift spell also deposits the spellcaster on the first layer of the plane.

All layers of a plane are connected to the Astral Plane, so travelers can reach specific layers directly through spells such as astral projection. Often the first layer is the one most hospitable to planar travelers.

Random Planar Destinations

Spells such as prismatic spray and dismissal may send an individual to a random plane. To determine where a character winds up, roll on the Random Planar Destinations table below, or on a table that better reflects the setting the DM is using.

The table assumes that the character’s plane of origin is either the Material Plane, the Astral Plane, the Ethereal Plane, or the Plane of Shadow. If the character’s plane of origin is instead one of the planes mentioned on the Random Planar Destinations table, then substitute the Material Plane for the plane of origin’s line on the table. For example, breaking a staff of power on the Elemental Plane of Fire sends the wielder to the Material Plane if a 91 is rolled.

The layer and exact location of an individual’s arrival on the particular plane is up to the DM. Transportation to a random plane does not guarantee survival there, and individuals who risk such effects should be aware of the dangers.

Plane Descriptions

The planes that make up the Great Wheel are briefly described below.

Each of the Transitive Planes and Inner Planes has its own random encounter table. The Outer Planes share four random encounter tables; use the appropriate one as directed in the plane’s description. All the encounter tables in this section are intentionally general; if you’re designing a site-based adventure on another plane, use the appropriate table as a starting point for your own encounters.

The Material Plane

The Material Plane is the center of most cosmologies and defines what is considered normal.

The Material Plane has the following traits:

• Normal gravity.
• Normal time.
• Alterable morphic.
• No Elemental or Energy Traits (specific locations may have these traits, however).
• Normal magic.

The Ethereal Plane

The Ethereal Plane is a misty, fog-bound dimension that is coexistent with the Material Plane and often other planes as well. Travelers within the Ethereal Plane describe the plane as a collection of swirling mists and colorful fogs. The Material Plane itself is visible from the Ethereal Plane, but it appears muted and indistinct, its colors blurring into each other and its edges turning fuzzy. Ethereal denizens watch the Material Plane as though viewing it through distorted and frosted glass.

While it is possible to see into the Material Plane from the Ethereal Plane, the Ethereal Plane is usually invisible to those on the Material Plane. Normally, creatures on the Ethereal Plane cannot attack creatures on the Material Plane, and vice versa. A traveler on the Ethereal Plane is invisible, incorporeal, and utterly silent to someone on the Material Plane. This makes the Ethereal Plane very useful for reconnaissance, spying on opponents, and other occasions when it’s handy to move around without being detected.

The Ethereal Plane is mostly empty of structures and impediments. However, the plane has its own inhabitants. Some of these are other ethereal travelers, but the ghosts found here pose a particular peril to those who walk the fog.

It has the following traits.

• No gravity.
• Alterable morphic. The plane contains little to alter, however.
• Mildly neutral-aligned.
• Normal magic. Spells function normally on the Ethereal Plane, though they do not cross into the Material Plane. It is possible for a caster on the Ethereal Plane to use a fireball spell against an enemy on the Ethereal Plane, but the same fireball wouldn’t affect anyone on the corresponding part of the Material Plane. A bystander on the Material Plane can walk through an ethereal battlefield without feeling more than the hair on the back of his neck standing up.

The only exceptions are spells and spell-like abilities that have the force descriptor, such as magic missile and wall of force, and abjuration spells that affect ethereal beings. Spellcasters on the Material Plane must have some way to detect foes on the Ethereal Plane before targeting them with force-based spells, of course. While it’s possible to hit ethereal enemies with a magic missile spell cast on the Material Plane, the reverse isn’t possible. No magical attacks cross from the Ethereal Plane to the Material Plane, including force attacks.

Example Ethereal Site: Misty Cemetery

Misty Cemetery (so named because the coastal fog at this location on the Material Plane often obscures the tombstones) is home to the ghosts of warlords from long-forgotten crusades. The ghosts menace wayward travelers and tomb robbers, but they are otherwise content to spend their time on the Ethereal Plane, biding their time until they can pass on to their final reward.

The ghosts rarely confront mourners or other cemetery visitors by daylight⁠—but anyone who visits the cemetery at night, defaces the crypts and tombs, or enters the Ethereal Plane invites their wrath. Their ringleaders are Durek of the Scar (Ftr 12), Colonel Harakh (Ftr 5/Clr 9), and the Eyeless One (Sor 16), but the cemetery is a vast, sprawling place, and the more powerful ghosts can’t be everywhere.

To draw a map of the Misty Cemetery, scatter small crypts across the landscape by drawing 10-foot-by-20-foot buildings with masonry walls and locked (Open Lock DC 30) iron doors. Place a tombstone in rows of adjacent squares (a tombstone functions as a slender pillar, providing a +2 bonus to Armor Class and a +1 bonus on Reflex saves). Occasionally pick two adjacent squares to represent an open grave (which functions as a trench). When faced with intruders on the Ethereal Plane, the ghosts will lurk within the crypts, trying to surprise the PCs by striking through the walls of the crypts.

Plane of Shadow

The Plane of Shadow is a dimly lit dimension that is both coterminous to and coexistent with the Material Plane. It overlaps the Material Plane much as the Ethereal Plane does, so a planar traveler can use the Plane of Shadow to cover great distances quickly. The Plane of Shadow is also coterminous to other planes. With the right spell, a character can use the Plane of Shadow to visit other realities.

The Plane of Shadow is a world of black and white; color itself has been bleached from the environment. It is otherwise appears similar to the Material Plane.

The sky on the Plane of Shadow is a black vault with neither sun nor stars. Landmarks from the Material Plane are recognizable on the Plane of Shadow, but they are twisted, warped things⁠—diminished reflections of what can be found on the Material Plane. Despite the lack of light sources, various plants, animals, and humanoids call the Plane of Shadow home.

The Plane of Shadow is magically morphic, and parts continually flow onto other planes. As a result, creating a precise map of the plane is next to impossible, despite the presence of landmarks. If a traveler visits a mountain range during one use of a shadow walk spell, the mountain range may still be there the next time, but the individual mountains may have moved about. Precision is a lost cause on the Plane of Shadow.

The Plane of Shadow has the following traits.

• Magically morphic. Spells such as shadow conjuration and shadow evocation modify the base material of the Plane of Shadow. The utility and power of these spells within the Plane of Shadow make them particularly useful for explorers and natives alike.
• Mildly neutral-aligned.
• Enhanced magic. Spells with the shadow descriptor are enhanced on the Plane of Shadow. Such spells are cast as though they were prepared with the Maximize Spell feat, though they don’t require the higher spell slots.

  Furthermore, specific spells become more powerful on the Plane of Shadow. Shadow conjuration and shadow evocation spells are 30% as powerful as the conjurations and evocations they mimic (as opposed to 20%). Greater shadow conjuration and greater shadow evocation are 70% as powerful (not 60%), and a shades spell conjures at 90% of the power of the original (not 80%).

• Impeded magic. Spells that use or generate light or fire may fizzle when cast on the Plane of Shadow. A spellcaster attempting a spell with the light or fire descriptor must succeed on a Spellcraft check (DC 20 + the level of the spell). Spells that produce light are less effective in general, because all light sources have their ranges halved on the Plane of Shadow.

Despite the dark nature of the Plane of Shadow, spells that produce, use, or manipulate darkness are unaffected by the plane.

Example Shadow Site: Dark City

When the characters enter the Plane of Shadow where it coexists with a Material Plane city, they find themselves in a dark, largely abandoned version of that town. The parallels are not exact, so the PCs’ favorite inn may be on a different street, be built in a different style, or lie in ruins.

Differences between a Material Plane city and its Plane of Shadow counterpart can be quite significant, such as a huge dark castle where none exists on the Material Plane, or an ancient battlefield where the city green should be. Most troubling of all are the shadowy echoes of people the traveler knows, shadow creatures with the twisted but still recognizable features of loved ones. These shadow duplicates do not speak and have no special abilities, but the effect is disconcerting nonetheless.

Shadow travelers in a place particularly familiar or meaningful to them must succeed on a DC 15 Will save to ignore such dark mirages. Those who fail are haunted and rattled by the similarities, taking a –⁠2 morale penalty on attack rolls and saving throws as long as they remain in a location familiar to them. Travelers who make their saves are unaffected by the dark mirages for the duration of their trip to the Plane of Shadow.

Not everything in a dark city is a mirage. Undead shadows glide through the streets looking for anyone who doesn’t belong amid the gloom, and bodaks that have found their way onto the Plane of Shadow stalk living travelers.

To draw a map for encounters in a dark city, start by drawing a normal cityscape (as described in the Urban Adventures section, page 98). Then reduce roughly one-quarter of the buildings to rubble (treat as large piles of stone and heavy debris strewn about). Another one-quarter of the buildings have some structural damage, such as gaping holes in the walls and collapsed roof timbers. Finally, move a few buildings into locations that don’t correspond with their Material Plane counterparts, and add and subtract a few streets and alleys.

The Astral Plane

The Astral Plane is the space between the planes. When a character moves through an interplanar portal or projects her spirit to a different plane of existence, she travels through the Astral Plane. Even spells that allow instantaneous movement across a plane, such as dimension door, briefly touch the Astral Plane.

The Astral Plane is a great, endless sphere of clear silvery sky, both above and below. Large tube-shaped clouds slowly coil into the distance, some appearing like thunderheads and others looking like immobile tornadoes of gray wind. Erratic whirlpools of color flicker in midair like spinning coins. Occasional bits of solid matter can be found here, but most of the Astral Plane is an endless, open domain.

Both planar travelers and refugees from other planes call the Astral Plane home. The most prominent denizens of the Astral Plane are the githyanki, an outcast race that preys on travelers throughout the plane.

The Astral Plane has the following traits.

• Subjective directional gravity.
• Timeless. Age, hunger, thirst, poison, and natural healing don’t function in the Astral Plane, though they resume functioning when the traveler leaves the Astral Plane.
• Mildly neutral-aligned.
• Enhanced magic. All spells and spell-like abilities used within the Astral Plane may be employed as if they were improved by the Quicken Spell feat. Already quickened spells and spell-like abilities are unaffected, as are spells from magic items. Spells so quickened are still prepared and cast at their unmodified level. As with the Quicken Spell feat, only one quickened spell can be cast per round.

Example Astral Site: Silver Sky

The characters are surrounded by a silver-gray haze that stretches endlessly in all directions. The map’s only feature is a colorful 10-foot-diameter pool that provides a natural portal to another plane (determined randomly). Some 70% of color pools are one-way portals.

If characters explore this part of the Astral Plane, they’ll discover more color pools that lead elsewhere. It takes 1d4×10 hours to find a color pool that leads to a particular plane.

But the PCs aren’t alone in the serene haze of the Astral Plane. Githyanki pirates cruise the color pools, looking for well-heeled travelers from other planes. A typical githyanki pirate ship is a longship (described on page 132 of the Player’s Handbook) that flies under its own power at a speed of 90 feet. The pirate captain (githyanki Ftr11 or Ftr6/Rog5) leads his crew into battle, with a war-wizard (githyanki Wiz9) or mercenary cleric (tiefling Clr9) providing support to the rank-andfile pirates. (Githyanki are never clerics themselves, so they must hire mercenary clerics because natural healing doesn’t work on the Astral Plane.)

The githyanki use the enhanced magic of the Astral Plane to good effect, taking full attacks, then using their dimension door spell-like ability as a free action to confound their enemies.

Elemental Plane of Air

The Elemental Plane of Air is an empty plane, consisting of sky above and sky below. Clouds billow up in bank after bank, swelling into grand thunderheads and dissipating into wisps like cotton candy. The wind pulls and tugs around travelers, and rainbows glimmer in the distance.

The Elemental Plane of Air is the most comfortable and survivable of the Inner Planes, and it is the home of all manner of airborne creatures. Indeed, flying creatures find themselves at a great advantage on this plane. While travelers without flight can survive easily here, they are at a disadvantage.

The Elemental Plane of Air has the following traits.

• Subjective directional gravity. Inhabitants of the plane determine their own “down” direction. Objects not under the motive force of others do not move.
• Air-dominant.
• Enhanced magic. Spells and spell-like abilities that use, manipulate, or create air (including spells of the Air domain) are both empowered and enlarged (as if the Empower Spell and Enlarge Spell metamagic feats had been used on them, but the spells don’t require higher-level slots).
• Impeded magic. Spells and spell-like abilities that use or create earth (including spells of the Earth domain and spells that summon earth elementals or outsiders with the earth subtype) are impeded.

Example Plane of Air Site: Cloud Island

What appears to be a white cumulus cloud is actually as solid as earth, if somewhat difficult to move across (treat as a shallow bog). Creatures with a fly speed can force themselves through the cloud island (effectively giving them a burrow speed of 10 feet). Some 2d4 pillars of fog 10 feet across drift across the landscape (they provide concealment as the obscuring mist spell, moving 10 feet in a random direction at initiative count 0). The cloud island is about ½ mile wide and 1d10×5 feet thick at any given point.

Floating in serene contemplation in the center of the cloud island is a noble djinn. If characters capture her (by defeating her without killing her or driving her away), she will grant three wishes collectively to the party. She is eager to talk to visitors from the Material Plane, where she spent more than a century trapped by an evil wizard. If characters can improve her attitude to friendly (it starts out indifferent), she’ll offer the characters a bargain. She will grant three wishes to the party if the characters will first avenge her imprisonment by capturing the evil Material Plane conjurer and returning him to this cloud island, where the djinn will arrange for “long-term detention.”

Elemental Plane of Earth

The Elemental Plane of Earth is a solid place made of rock, soil, and stone. An unwary and unprepared traveler may find himself entombed within this vast solidity of material and have his life crushed into nothingness, his powdered remains a warning to any foolish enough to follow.

Despite its solid, unyielding nature, the Elemental Plane of Earth is varied in its consistency, ranging from relatively soft soil to veins of heavier and more valuable metal. Striations of granite, volcanic rock, and marble interweave with brittle crystal and soft, crumbling chalks and sandstones. Thin veins of gemstones, rough and huge, can be found within the plane, and these unpolished jewels often lead the greedy to this plane in the hope of picking them up with minimal effort. Such prospectors often meet their match in the natives of the Elemental Plane of Earth, who feel extremely attached (sometimes literally) to parts of their home.

The Elemental Plane of Earth has the following traits.

• Earth-dominant.
• Enhanced magic. Spells and spell-like abilities that use, manipulate, or create earth or stone (including those of the Earth domain) are both empowered and extended (as if the Empower Spell and Extend Spell metamagic feats had been used on them, but the spells don’t require higher-level slots). Spells and spell-like abilities that are already empowered or extended are unaffected by this benefit.
• Impeded magic. Spells and spell-like abilities that use or create air (including spells of the Air domain and spells that summon air elementals or outsiders with the air subtype) are impeded.

Example Plane of Earth Site: Great Dismal Delve

Essentially a dungeon the size of a continent, the Great Dismal Delve is a maddening maze of passages that are intentionally bewildering to the traveler. A variety of powerful genie lords and their slave races live here in dark splendor, eagerly mining gems for trade. Slaves, often the losers in bets and bargains with the rulers of the Great Dismal Delve, build and rebuild passages, fend off elemental attacks, and are otherwise slowly worked to death by their uncaring masters.

Glowing crystals line the Great Dismal Delve, and great vaults are set with them in star patterns unlike any seen on the Material Plane. The Great Dismal Delve spans a number of large, natural caverns that are tectonically unstable. Earthquakes (with an effect as the earthquake spell) are frequent occurrences, which keeps the slaves busy doing repair work.

The connections and passages of the Great Dismal Delve link up with a complicated array of portals leading to other Inner Planes, the subterranean reaches of some of the Outer Planes, and the deepest dungeons of the Material Plane. It is rumored that somewhere within the Great Dismal Delve is a freestanding portal to almost every secret location within the D&D cosmology.

A map of the Great Dismal Delve looks like any dungeon, only it stretches far beyond what’s available on the Material Plane. The Great Dismal Delve is a mix of natural caverns and finely worked passageways. Doors, corridors, and rooms are as likely to be trapped as they are in the deadliest dungeon, and almost any monster can be found either lurking in its lair or stalking the PCs through the hallways.

Elemental Plane of Fire

Everything is alight on the Elemental Plane of Fire. The ground is nothing more than great, evershifting plates of compressed flame. The air ripples with the heat of continual firestorms, and the most common liquid is magma, not water. The oceans are made of liquid flame, and the mountains ooze with molten lava. The plane is a crematorium for the unprepared traveler and an uncomfortable spot even for the dedicated adventurer.

Fire survives here without need for fuel or air, but flammables brought onto the plane are consumed readily. The elemental fires seem to feed on each other to produce a continually burning landscape.

The Elemental Plane of Fire has the following traits.

• Fire-dominant.
• Enhanced magic. Spells and spell-like abilities with the fire descriptor are both maximized and enlarged (as if the Maximize Spell and Enlarge Spell had been used on them, but the spells don’t require higher-level slots). Spells and spell-like abilities that are already maximized or enlarged are unaffected by this benefit.
• Impeded magic. Spells and spell-like abilities that use or create water (including spells of the Water domain and spells that summon water elementals or outsiders with the water subtype) are impeded.

Example Plane of Fire Site: City of Brass

The City of Brass is populated by powerful efreet and is considered by many efreet to be their home and their capital. Efreet may be found elsewhere on the Elemental Plane of Fire, but even farflung settlements owe fealty and allegiance to the grand sultan who rules the City of Brass from his burning palace. The grand sultan is said to be an efreeti of singular power and prowess, and is advised by all manner of elemental nobles. His direct servants, both in the city and on the Material Plane, are six lords of considerable power.

The city is cradled in a brass hemisphere 40 miles across, floating above a plate of cracked obsidian at the heart of the Elemental Plane of Fire. Stairs of burning basalt and rivers of flame stream up from the surface below to the well-armed gates of the city. The city walls may be breached by flying creatures, but the efreet take a dim view of interlopers who refuse to present themselves at one of the city’s gates.

The City of Brass is the best known location on the Elemental Plane of Fire and is also the most likely to be visited by travelers from the Material Plane. The air is slightly cooler here; it deals no damage (unlike everywhere else on this fire-dominant plane), but it is still stiflingly hot. That doesn’t mean the City of Brass is particularly hospitable. Every brass wall glows with heat, and casual contact with the walls deals 1d6 points of fire damage per round.

Even the iron cobblestones glow with heat, dealing 1 point of fire damage per round. Without the aid of magic, visitors soon writhe and burn in the streets.

The City of Brass has the mildly evil-aligned trait. Good-aligned creatures within the City of Brass take a –⁠2 penalty on all Charisma-based checks. This alignment trait is due in part to the nature of the efreet within the walls, but the city also has a number of freestanding portals leading to the Nine Hells of Baator. Devils are common within the walls of the City of Brass, either performing missions for their infernal masters or bringing tribute and gifts to the grand sultan’s court.

To make an encounter map for the City of Brass, use the guidelines in the Urban Adventures section (page 98), but the buildings are half again as tall as they would be in a Material Plane city, and most have a plethora of exterior staircases, ledges, and balconies. Include some pools of magma, which deals 2d6 points of fire damage to characters who wade through it and 20d6 points of fire damage to creatures who are fully immersed. Some pedestals and sconces spout blasts of flame every 1d4 rounds (dealing 5d6 points of fire damage to everyone within 20 feet at initiative count 0; Reflex DC 14 half ).

At the center of the city are its tallest towers and greatest fountains of flame. Here is the Burning Palace of the Grand Sultan of All the Efreet, where he rules from the Charcoal Throne. It is said that within the great palace are wonders beyond belief and treasure beyond counting. But here also is found death for any uninvited guest who seeks to wrest even a single coin or bauble from the treasure rooms of the grand sultan.

Elemental Plane of Water

The Elemental Plane of Water is a sea without a floor or a surface, an entirely fluid environment lit by a diffuse glow. It is one of the more hospitable of the Inner Planes once a traveler gets past the problem of breathing the local medium.

The eternal oceans of this plane vary between ice cold and boiling hot, between saline and fresh. They are perpetually in motion, wracked by currents and tides. The plane’s permanent settlements form around bits of flotsam and jetsam suspended within this endless liquid. These settlements drift on the tides of the Elemental Plane of Water.

The Elemental Plane of Water has the following traits.

• Subjective directional gravity. The gravity here works similar to that of the Elemental Plane of Air. But sinking or rising on the Elemental Plane of Water is slower (and less dangerous) than on the Elemental Plane of Air.
• Water-dominant.
• Enhanced magic. Spells and spell-like abilities that use or create water are both extended and enlarged (as if the Extend Spell and Enlarge Spell metamagic feats had been used on them, but the spells don’t require higher-level slots). Spells and spell-like abilities that are already extended or enlarged are unaffected by this benefit.
• Impeded magic. Spells and spell-like abilities with the fire descriptor (including spells of the Fire domain) are impeded.

Example Water Site: Sargasso Doldrum

A spherical tangle of kelp and seaweed a mile across, the sargasso doldrum is home to many dangerous predators that feed on the herbivorous fish that eat the seaweed.

Characters who explore the sargasso doldrum find it tough going. Even if they have a swim speed, it takes 2 squares of movement to struggle through each square in the web of kelp. Only those with a freedom of movement or pass without trace spell can move normally through the area. Line of sight is limited to 30 feet, and creatures more than 20 feet away have concealment.

The sargasso doldrum is infested with dire sharks, who attack in great hunting schools without regard to their own safety. More sinister foes such as aboleths and black dragons study interlopers as they fight the sharks, deciding how best to hunt them if they stay among the seaweed.

A ruined war galley sits in the center of the sargasso doldrum. The ship, protected by a neutral alignment, maximized forbiddance spell, holds the treasure trove of a powerful water naga wizard. The aboleths and black dragons don’t know what’s in the ship’s hold; they would just hire neutral creatures to extract the riches if they found out what they could gain.

To draw an encounter map for the doldrums, include some irregular clusters of adjacent squares roughly 15 feet across. These squares, representing particularly dense clots of sargasso, function as heavy undergrowth.

Negative Energy Plane

To an observer, there’s little to see on the Negative Energy Plane. It is a dark, empty place, an eternal pit where a traveler can fall until the plane itself steals away all light and life.

The Negative Energy Plane is the most hostile of the Inner Planes, and the most uncaring and intolerant of life. Only creatures immune to its life-draining energies can survive there.

The Negative Energy Plane has the following traits.

• Subjective directional gravity.
• Major negative-dominant. Some areas within the plane have only the minor negative-dominant trait, and these islands tend to be inhabited.
• Enhanced magic. Spells and spell-like abilities that use negative energy are maximized (as if the Maximize Spell metamagic feat had been used on them, but the spells don’t require higher-level slots). Spells and spell-like abilities that are already maximized are unaffected by this benefit. Class abilities that use negative energy, such as rebuking and controlling undead, gain a +10 bonus on the roll to determine Hit Dice affected.
• Impeded magic. Spells and spell-like abilities that use positive energy, including cure spells, are impeded. Characters on this plane take a –⁠10 penalty on Fortitude saving throws made to remove negative levels bestowed by an energy drain attack.

Random Encounters: Because the Negative Energy Plane is virtually devoid of creatures, random encounters on the plane are exceedingly rare.

Example Negative Plane Site: Voidstone Field

In some locations on the Negative Energy Plane, the collapsing intensity of the plane is so great that the negative energy folds in on itself, stabilizing into solid chunks of utterly black matter. These chunks of voidstone might be the building blocks of such items as the sphere of annihilation. Indeed, anything that comes into contact with a voidstone is destroyed in seconds.

Unlike with a sphere of annihilation, a character touching a piece of voidstone gets a DC 25 Fortitude save each round he or she stays in contact with it. Natives of the Negative Energy Plane are vulnerable to voidstones.

A chunk of voidstone cannot be controlled through mental energy as a sphere of annihilation can be.

Voidstones may be of any size, ranging from inches across to dozens of feet. To draw them on an encounter map, put small dots (representing very small voidstones roughly 1 foot in diameter) in about 5% of the squares. Draw 3d6 voidstones that take up a whole square each, and add 1d4 very large voidstones that are 10 feet or more in diameter.

The very small and very large voidstones are stationary, but the square-sized voidstones move. Each round at initiative count 0, each square-sized voidstone moves 1d3 squares toward the nearest living creature.

Nightwalkers lurk among the voidstones, which act as an alarm system for them (the voidstones stay stationary because the nightwalkers are undead). PCs who fight the nightwalkers will also have to contend with the inexorable approach of the voidstones. The nightwalkers have learned to use the unusual terrain in other ways; they’ll use their heft to bull-rush foes into oblivion, for example.

Positive Energy Plane

The Positive Energy Plane is best compared to the heart of a star. It is a continual furnace of creation, a domain of brilliance beyond the ability of mortal eyes to comprehend. Its very being wavers and ripples as new matter and energy is born and swells to full power like a bursting fruit. It is a vibrant plane, so alive with itself that travelers themselves are empowered by visiting it.

The Positive Energy Plane has no surface and is akin to the Elemental Plane of Air with its wide-open nature. However, every bit of this plane glows brightly with innate power. This power is dangerous to mortal forms, which are not made to handle it.

Despite the beneficial effects of the plane, it is one of the most hostile of the Inner Planes. An unprotected character on this plane swells with power as positive energy is force-fed into her. Then, her mortal frame unable to contain that power, she immolates as if she were a small planet caught at the edge of a supernova. Visits to the Positive Energy Plane are brief, and even then travelers must be heavily protected.

The Positive Energy Plane has the following traits.

• Subjective directional gravity.
• Major positive-dominant. Some regions of the plane have the minor positive-dominant trait instead, and those islands tend to be inhabited.
• Enhanced magic. Spells and spell-like abilities that use positive energy, including cure spells, are maximized (as if the Maximize Spell metamagic feat had been used on them, but the spells don’t require higher-level slots). Spells and spell-like abilities that are already maximized are unaffected by this benefit. Class abilities that use positive energy, such as turning and destroying undead, gain a +10 bonus on the roll to determine Hit Dice affected. (Undead are almost impossible to find on this plane, however.)
• Impeded magic. Spells and spell-like abilities that use negative energy (including inflict spells) are impeded.

Random Encounters: Because the Positive Energy Plane is virtually devoid of creatures, random encounters on the plane are exceedingly rare.

Example Positive Plane Site: Burst Cluster

Even among the brilliant and deadly radiance of the Positive Energy Plane, some regions are more intense and dangerous than others. These regions erupt like miniature suns, suddenly granting those within the burst radius (usually 30 feet, but occasionally up to 120 feet) an additional 3d10 temporary hit points. The dangers of exceeding double one’s full normal hit points (as noted for the positive-dominant trait) still apply.

In addition, those within an energy burst must make a DC 24 Fortitude save or be blinded for 1d10 rounds.

Ravids sometimes patrol the periphery of burst clusters, confident that their high speed will get them out of danger before a burst makes them explode.

Heroic Domains of Ysgard

Ysgard is a plane on an epic scale, with soaring mountains, deep fjords, and dark caverns that hide the secret forges of the dwarves. A biting wind always blows at a hero’s back. From the freezing water channels to the sacred groves of Alfheim’s elves, Ysgard’s terrain is grand and terrible. It is a place of sharp seasons: Winter is a time of darkness and killing cold, and a summer day is scorching and clear.

Most spectacular of all, the landscape floats atop immense rivers of earth flowing forever through an endless skyscape. The broadest earthen rivers are the size of continents, while smaller sections, called earthbergs, are island-sized. Fire rages under each river, but only a reddish glow penetrates to the continent’s top. Of more concern is the occasional collision between rivers, which produces terrible quakes and sometimes spawns new mountain ranges.

Ysgard is the home of slain heroes who wage eternal battle on fields of glory. When these warriors fall, they rise again the next morning to continue eternal warfare.

The plane boasts two layers beneath the top layer, also called Ysgard: the fiery caverns of Muspelheim and the underground forests of Nidavellir.

Ysgard has the following traits.

• Infinite size. Ysgard goes on forever, but its well-known realms have boundaries within the plane as a whole.
• Divinely morphic. Specific powerful beings (such as the deities Kord and Olidammara) can alter Ysgard with a thought. Ordinary creatures find Ysgard as easy to alter as the Material Plane is⁠—they can be affected by spells and physical effort normally. But deities can change vast areas, creating great realms for themselves.
• No elemental traits. No one element dominates on Ysgard; all are in balance, as on the Material Plane. However, parts of the second layer, Muspelheim, are treated as if they possessed the fire-dominant trait.
• Minor positive-dominant. Ysgard possesses a riotous explosion of life in all its forms. All individuals on a positive-dominant plane gain fast healing 2 and may even regrow lost limbs in time. Additionally, those slain in the never-ending conflicts on Ysgard’s fields of battle rise each morning as if true resurrection had been cast on them, fully healed and ready to fight anew. Only those who suffer mortal wounds on Ysgard’s battlefields get the true resurrection effect; dead characters brought to Ysgard don’t spontaneously revive.
• Mildly chaos-aligned. Lawful creatures on Ysgard take a –⁠2 penalty on all Charisma-based checks.

Random Encounters: Use the Beatific Encounters table (page 167) for random encounters on Ysgard.

Example Ysgard Site: Plain of Ida

This great field is located near the great free city of Himinborg, the largest population center on Ysgard’s top layer. The Plain of Ida hosts daily festivals where warriors can flaunt their mettle. Here, bravery and skill in battle is valued over all else. It’s also a battlefield where rival armies clash by day only to revel in Himinborg’s taverns by night.

Characters who wind up on the Plain of Ida are as likely to be thrust into the maelstrom of a battle as they are to explore the carnival atmosphere of a “festival of steel.”

To draw a map for a mass battle, use the battlefield guidelines in the Plains Terrain section. The combatants on the Plain are generally mercenary companies that wander the Planes. Because soldiers rise the next morning, the Plain of Ida is a useful tool for units that want to hone their mass-battle skills.

Almost any kind of creature can be found on the battlefield. A phalanx of dwarves might stand resolute against an assault by halfcelestial giants. A horde of slaadi might overrun githyanki mercenaries, only to be routed by dragon-mounted githyanki reinforcements. If the characters find themselves in the middle of a battle, they’ll have to combine diplomacy with combat prowess to avoid being crushed by both sides.

Major battles happen only one day in three, on average. Festivals are common on the other days, featuring a variety of sideshows, midway booths, and merchants surrounding the main event, which is always a test of martial prowess. Sword duels, jousts on exotic steeds, wrestling matches, archery tourneys, and even grand tugs-of-war are common on the Plain of Ida, with many spectators and participants traveling from Himinborg. The prizes are often substantial, but the competition is fierce. The festivals attract fairgoers from across the Great Wheel, so they always offer diversions and intrigues for the less athletically minded.

With a guaranteed true resurrection if they fall, many characters will find battles on the Plain of Ida too tempting to pass up. Defeat still has its price, however, because victorious armies often loot the bodies of the fallen. Some characters might lose but not technically die (being turned to stone, banished from the plane entirely, or taken prisoner).

Ever-Changing Chaos of Limbo

Limbo is a plane of pure chaos. Untended sections appear as a roiling soup of the four basic elements and all their combinations. Balls of fire, pockets of air, chunks of earth, and waves of water battle for ascendancy until they in turn are overcome by yet another chaotic surge. Landscapes similar to ones found on the Material Plane drift through the miasma: bits of forest, meadow, ruined castles, and small islands. Despite the plane’s inhospitable environment, the slaadi and the githzerai call Limbo home.

Limbo has no layers. Or, if it does, the layers continually merge and part, each is as chaotic as the next, and even the wisest sages would be hard-pressed to distinguish one from another.

Limbo has the following traits.

• Subjective directional gravity.
• Highly morphic. Limbo is continually changing, and keeping a particular area stable is difficult. A given area, unless magically stabilized somehow, can react to specific spells or sentient thought. Left alone, it continually changes. For more information, see Raw Limbo under Limbo Terrain, below.
• Sporadic element-dominant. No one element constantly dominates Limbo. Each element (air, earth, fire, and water) is dominant from time to time, so any given area is a chaotic, dangerous boil. The elemental dominance can change without warning.
• Strongly chaos-aligned. This trait does not apply within the walls of githzerai monasteries (but it does apply in githzerai cities).
• Wild magic. Spells and spell-like abilities function normally within permanent structures or on permanently stabilized landscapes in Limbo. However, any spell or spell-like ability used in an untended area of Limbo, or an area temporarily controlled, has a chance to go awry. The spellcaster must make a level check (1d20 + spellcaster level) against a DC of 20 + the level of the attempted spell. If the caster fails the check, roll on the Wild Magic table to determine the exact effect.

Random Encounters: Alternate between the Beatific Encounters table and the Abyssal Encounters table (page 167) for random encounters in Limbo.

Limbo Terrain

There are two kinds of terrain in Limbo. The vast majority of the plane is uncontrolled, raw Limbo, but here and there are islands of more stable terrain⁠—usually earth, but sometimes another material.

Raw Limbo: To draw an encounter map of raw Limbo, scatter irregular areas of fire, water, earth, and high winds across the grid. As a rough guide, make each area roughly 40 feet square and put a 15-foot gap between areas. But because this is the plane of ultimate chaos, you should vary widely from this guideline.

Roughly one-quarter of the areas are fire-dominant (dealing 3d10 points of damage per round and setting characters on fire), one-quarter are water-dominant (essentially free-floating blobs of water), one quarter are air-dominant tornadoes (as described on page 94), and one-quarter are simply earth.

Every round, at initiative count 0, the areas of raw Limbo shift. For each area, roll 1d8. This determines the direction that a particular area will shift, with 1 being back toward the top of the map and 2 through 8 counting clockwise in 45-degree increments. Then, shift the entire area 1d4 squares in that direction.

If fire-dominant and water-dominant areas overlap after the shift, they cancel each other out within the area of the overlap, changing the shape of both areas and leaving the area of the overlap outside both areas. The same thing happens if an air-dominant and earth-dominant area overlap. Other overlaps (fire and earth, for example) have the full effects of both elements in the overlap area.

Stable Areas: Most of Limbo’s living inhabitants remain in the stable areas free of the plane’s shifting elements. Often these stable areas are chunks of earth and stone up to a half-mile across. Occasionally a lake of stable water, or a massive, roiling firestorm will appear.

Example Limbo Site: Monastery of Zerth’Ad’lun

One of many githzerai monasteries on the plane, Zerth’Ad’lun follows the teaching of Sensei Belthomias, a 16th-level monk. Belthomias teaches a specialized martial art (as do many monasteries), and those students who fully embrace his teachings are also called Zerth cenobites. Those who practice zerthi—“Zerth’s teaching” in the githzerai tongue—claim to peer a moment into the future in order to aid their martial expertise.

From the exterior, the monastery appears almost like a small glade of stone spires and towers layered around a sphere about a quarter-mile in diameter. Taking full advantage of the subjective gravity of Limbo, the interior of the monastery has winding stairs that connect “floors” to “walls” or “ceilings.” All the surfaces are really floors for those who don’t mind adjusting their own subjective orientation.

Vast halls provide room for mass martial arts training, while hundreds of tiny cells lighted by dim candles provide privacy for individual meditations. The schedule of a monk at Zerth’Ad’lun is strict and harsh, but the rewards of the spirit are considered sufficient compensation.

Mapping the monastery⁠—even enough of it for an encounter—is difficult because the best frame of reference seems to change from square to square. Simply throw in as many dungeon elements as you can, making sure to rotate some and turn others upside down. If the characters fight the monks of the monastery, have the monks jump from ceiling to wall, using subjective gravity to right themselves when they land.

The monastery welcomes visitors and may put them up for as long as a week in quarters set aside for hospitality. Nongithzerai who are interested in studying at the monastery are allowed to do so—Belthomias is impressed by any nongithzerai who can survive Limbo long enough to find the monastery. The supplicant must be willing to spend a few months in the monastery learning the basics and abiding the schedule of a cenobite. Then Belthomias poses a series of three tests, one of which involves fighting slaadi, one of which involves controlling Limbo, and one of which involves a quest to the Material Plane (often to the subterranean homes of the mind flayers).

Windswept Depths of Pandemonium

Pandemonium is a great mass of matter pierced by innumerable tunnels carved by the howling winds of the plane. It is windy, noisy, and dark, having no natural source of light. The wind quickly extinguishes normal fires, and lights that last longer draw the attention of wights driven insane by the constant howling wind.

Every word, scream, or shout is caught by the wind and flung through all the layers of the plane. Conversation is accomplished by shouting, and even then words are spirited away by the wind before they travel farther than 10 feet.

The stale wind of Pandemonium is cold, and it steals heat from unprotected travelers. The endless gale buffets each inhabitant, blowing sand and dirt into eyes, snuffing torches, and carrying away loose items. In some places, the wind howls so fiercely that it lifts creatures off their feet and carries them for miles before dashing their forms against some dark cliff face.

In a few relatively sheltered places, the wind dies down to just a breeze carrying haunting echoes from distant parts of the plane, though these sounds are so distorted that they sound like cries of torment.

Pandemonium has four layers: Pandesmos, Cocytus, Phlegethon, and Agathion. Pandesmos, the highest layer, has large caverns and passageways, with Cocytus and Phlegethon having progressively smaller and more rugged caverns. Agathion has only isolated caverns, with no tunnels linking them.

Pandemonium has the following traits.

• Objective directional gravity. In the cavernous tunnels of Pandemonium, gravity is oriented toward whatever wall a creature is nearest. Thus, there is no normal concept of floor, wall and ceiling—any surface is a floor if you’re near enough to it. Rare narrow tunnels exactly cancel out gravity, allowing a traveler to shoot through them at incredible speed. The layer of Phlegethon is an exception—there, the normal gravity trait applies.
• Divinely morphic. Specific powerful beings such as the deity Erythnul can alter Pandemonium. Ordinary creatures find Pandemonium indistinguishable from the Material Plane (it has the alterable morphic trait for them, in other words). Spells and physical effort affect Pandemonium normally.
• Mildly chaos-aligned.

Random Encounters: Use the Abyssal Encounters table (page 167) for random encounters in Pandemonium.

Example Pandemonium Site: Howler’s Crag

Howler’s Crag is a jumbled pile of stones, boulders, and worked stone, as if a giant’s palace had collapsed in on itself, standing in the center of Cocytus. The Crag’s top is a mostly level platform about 10 feet in diameter, with a low wall surrounding it. The platform and those on it glow with an ephemeral blue radiance. The lower reaches of the Crag are riddled with small burrows. Some are dead ends, but others connect. The wall of every burrow is covered with writing in lost alphabets that supposedly spells out strange psalms, liturgies, and strings of numerals or formulas.

Natives of Pandemonium say that anything yelled aloud from the top of the Crag finds the ears of the intended recipient, no matter where that recipient is on the Great Wheel. The words of the message are borne on a shrieking, frigid wind.

Demons of various sorts have learned that visitors constantly trickle to the Crag. The visitors are usually archaeologists, diviners, or those wishing to send a message to some lost friend or enemy. Most become the prey of the ambushing fiends.

Howler’s Crag is large enough to provide its own gravity; characters can simply walk up it without needing to climb. To make an encounter map for Howler’s Crag, draw it as if the Crag were the floor (covered in dense rubble). Include a number of burrows, which are each 10 feet in diameter. The fiends that waylay travelers (often hezrous and nalfeshnees) will emerge from the burrows when they sense the presence of visitors.

As elsewhere on Pandemonium, a fight on Howler’s Crag takes place among strong winds. Attacks with ranged weapons have a –⁠2 penalty due to the winds, and a Tiny or smaller creature must succeed on a DC 10 Fortitude save each round or be knocked down.

Sometimes the winds that buffet Howler’s Crag are even more powerful. For the effects of stronger winds on combat, see page 95.

Infinite Layers of the Abyss

The Abyss is all that is ugly, all that is evil, and all that is chaotic reflected in infinite variety through layers beyond counting. Its virtually endless layers spiral downward into ever more atrocious forms. Conventional wisdom places the number of layers of the Abyss at 666, though there may be far more. The whole point of the Abyss, after all, is that it’s far more terrible than conventional wisdom could ever encompass.

Each layer of the Abyss has its own unique, horrific environment. No theme unifies the multifarious layers other than their harsh, inhospitable nature. Lakes of caustic acid, clouds of noxious fumes, caverns of razor-sharp spikes, and landscapes of magma are all possibilities. So are less immediately deadly terrains such as parched salt deserts, subtly poisonous winds, and plains of biting insects.

The Abyss is home to demons, creatures devoted to death and destruction. A demon in the Abyss looks upon visitors as food or a source of amusement. Some see powerful visitors as potential recruits (willing or not) in the never-ending war that pits demons against devils, known as the Blood War.

The Abyss has the following traits.

• Normal gravity. The top layer of the Abyss (called the Plain of Infinite Portals) and many other layers have the normal gravity trait, but other layers of the Abyss can contain different gravity traits.
• Normal time. Time flows at the same rate in the Abyss as on the Material Plane. However, rumors persist of a layer where time flows backward with regard to aging. The reverse flow is erratic, however, and a visitor could be reverse-aged to childhood or out of existence altogether.
• Divinely morphic. Entities at least as powerful as lesser deities can alter the Abyss. Less powerful creatures find the Abyss indistinguishable from a normal Material Plane (the alterable morphic trait) in that the plane can be changed by spells and physical effort.
• Mixed elemental and energy traits. This trait varies widely from layer to layer. In the Abyss as a whole, no one element or type of energy constantly dominates, though certain layers have a dominant element or energy, or a mixture of two or more.
• Mildly chaos-aligned and mildly evil-aligned.

Random Encounters: Use the Abyssal Encounters table (page 167) for random encounters in the Abyss.

Random Abyssal Layers

What if your characters wind up being sent to the Abyss as a result of an adventure gone wrong? Or what if they flee powerful demons by jumping through the nearest portal?

Use the following table to randomly determine the general characteristics of an unknown layer. If desired, roll twice (or more) and combine the results.

Example Abyss Site: Demonweb Pits

The 66th layer of the Abyss is home to Lolth, the Spider Queen. The plane folds in upon itself so that it resembles a great web. A dizzying array of web pathways interconnect with fractal complexity. Each strand is strung with portals onto the planes where Lolth is worshiped. Lolth’s palace is said to be a mobile iron stronghold shaped like a spider, perpetually crawling across her planar web.

To draw an encounter map for the Demonweb Pits, design a crisscrossing network of 20-foot-wide walkways suspended magically in vast cloud of solid fog (as the spell). The fog stays 1d4×10 feet away from the pathways, so characters can sometimes glimpse other parts of the web that are above, below, or to the side of the path they’re walking on.

The web twists and turns in on itself, but it always appears perfectly level, even when it corkscrews upward or downward. It’s possible to make four right turns and wind up underneath the point where you started, without encountering a slope or stairs. Characters who fall⁠—or are bull rushed⁠—off a walkway fall at only 60 feet per round (as the feather fall spell), and they take no damage when they land on another walkway (which might be miles below where they started).

Tarterian Depths of Carceri

The prison plane of Carceri seems the least overtly dangerous of the lower planes, but that first impression quickly disappears. Acid seas and sulfurous atmospheres may be rare on this plane, and no areas of biting cold or infernos of raging heat exist. The danger of Carceri is a subtler thing.

The plane is a place of darkness and despair, of passions and poisons, and of kingdom-shattering betrayals. On Carceri, hatreds run like a deep, slow-moving river. And there’s no telling what the flood of treachery is going to consume next. It is said that a prisoner on Carceri may only escape when she has become stronger than whatever imprisoned her there. That’s a difficult task on a plane whose very nature breeds despair, betrayal, and self-hatred.

Carceri consists of six layers: Orthrys, Cathrys, Minethys, Colothys, Porphratys, and Agathys. Each layer consists of a series of orbs like tiny planets. A gulf of air separates each orb from the next. On a particular layer, little distinguishes one orb from the next, and it’s possible that the number of orblike planets on each layer is infinite.

Carceri has the following traits.

• Normal gravity. On the orbs, gravity is normal. Between orbs, there is no gravity, which eases travel for those who can fly beyond the clutches of each orb’s gravity.
• Divinely morphic. Nerull and any other entity of lesser deity status or greater can alter Carceri. More ordinary creatures find Carceri indistinguishable from the Material Plane; it responds to spells and physical effort normally.
• Mildly evil-aligned.

Random Encounters: Use the Abyssal Encounters table (page 167) for random encounters on Carceri.

Example Carceri Site: Sand Tombs of Payratheon

Payratheon is the name of a vanished city built on an orb of Minethys eons ago. That city is long buried under sand dunes, but its sand-drowned avenues, crumbled towers, and silted porticos still remain far below the shifting surface of the layer. Sometimes the shifting sands reveal Payratheon for an hour or a longer, but it is always engulfed again by the sands, smothering most creatures that were tempted by its appearance and entered the sand-blasted city.

Resourceful adventurers have burrowed down to find outlying suburbs of the city during its phases of submersion. Tales of terror walk hand in hand with these accounts, which tell of dragonlike “sand gorgons” that swim through the sand as if it were water. Also mentioned are the remnants of former inhabitants that force their way through the streets as petrified undead, so weathered and eroded that little can be discerned of their original race or size.

To create an encounter map for the sand tombs, start with a city, then reduce half the buildings to heavy rubble and damage the others in some significant way. The riches of Payratheon are there for the taking, for the city was buried suddenly. But the characters will have to contend with the sand gorgons (24 HD gorgons with a burrow speed of 30 feet), mummy lords (see the Monster Manual), and other undead eager to slay and consume the living. And they’re also racing against time⁠—a titanic sandstorm is only 1d4 hours away.

Gray Waste of Hades

Hades sits at the nadir of the lower planes, halfway between two races of fiends each bent on the other’s annihilation. Thus, it often sees its gray plains darkened by vast armies of demons battling equally vast armies of devils who neither ask nor give quarter. If any plane defines the nature of true evil, it is the Gray Waste.

In the Gray Waste of Hades, pure undiluted evil acts as a powerful spiritual force that drags all creatures down. Here, even the consuming rage of the Abyss and the devious plotting of the Nine Hells are subjugated to hopelessness. Apathy and despair seep into everything at the pole of evil. Hades slowly kills a visitor’s dreams and desires, leaving the withered husk of what used to be a fiery sprit. Spend enough time in Hades, and a visitor gives up on things that used to matter, eventually succumbing to total apathy.

Hades has three layers, called “glooms”: Oinos, Niflheim, and Pluton. Uncaring malevolence that slowly crushes the spirit permeates each gloom.

Hades has the following traits.

• Divinely morphic. Entities of at least lesser deity status can alter Hades, though few deities care to reign in Hades. The Gray Waste has the alterable morphic trait for less powerful creatures; Hades responds normally to spells and physical effort.
• Strongly evil-aligned.
• Entrapping. This is a special trait unique to Hades (although Elysium has a similar entrapping trait). A nonoutsider in Hades experiences increasing apathy and despair while there. Colors become grayer and less vivid, sounds duller, and even the demeanor of companions seems to be more hateful. At the conclusion of every week spent in Hades, any nonoutsider must succeed on a Will saving throw (DC 10 + the number of consecutive weeks in Hades). Failure indicates that the individual has fallen entirely under the control of the plane, becoming a petitioner of Hades.

Travelers entrapped by the inherent evil of Hades cannot leave the plane of their own volition and have no desire to do so. Memories of any previous life fade into nothingness, and it takes a wish or miracle spell to return such characters to normal.

Random Encounters: Alternate between the Abyssal Encounters table and the Hellish Encounters table (page 167) for random encounters in Hades.

Example Hades Site: Underworld

On the gloom of Pluton, the Underworld is contained within walls of gray marble that stretch for hundreds of miles and are visible for thousands of miles beyond that. Sometimes the souls of creatures who have died particularly tragic deaths come here, rather than traveling onward to their final reward.

A single double gate pierces the marble walls of the realm. Constructed of beaten bronze, the gates are dented and scarred by heroes intent on getting past. However, the gates are also guarded by a terrible fiendish beast, a Gargantuan three-headed hound made from the squirming, decaying bodies of hundreds of dead spirits.

Beyond the gate, the inside of the realm appears much like the outside. Blackened trees, stunted bushes, and wasted ground dominate the landscape. To draw an encounter map for the Underworld, use the guidelines for sparse forest, but replace any undergrowth with light rubble. Gray, wraithlike spirits wander through this realm, on the verge of being sucked completely dry of all emotion by the spiritual decay of the plane. When they lose the last shred of emotion, their remaining essence becomes one with the gloom of Pluton.

Sometimes, great heroes or desperate lovers from the Material Plane travel to this layer via a tributary of the River Styx or portals hidden in great volcanic fissures. They come to the Underworld because they believe that they can find the spirit of a friend or loved one and extricate that spirit from a hopeless eternity. The hound can’t be bargained with, but if the characters manage to get inside, they’ll have to negotiate with powerful ghosts and outsiders to find the soul they’re looking for. Whatever the characters seek here, the Underworld is sure to exact a price.

Bleak Eternity of Gehenna

Gehenna’s top layer borders Hades and the Nine Hells, so it is not a pleasant place. Floating in an impenetrable, infinite void are volcanic mountains seemingly without base or peak. They are only finite in the strictest sense of the word, measuring hundreds of thousands of miles in each direction. A single volcanic mountain dominates each of the four layers of Gehenna, though lesser volcanic earthbergs drift and sometimes smash into the greater mountains.

No naturally occurring level place exists in any of the layers; all the slopes are at least 45 degrees, and many are akin to sheer cliffs. Gehenna’s fiendish inhabitants have carved artificial ledges, some large enough for entire cities, and switchback paths to connect them. But those edifices have a tendency to break apart, sending their builders on a long, sliding fall down the mountain.

Gehenna’s four layers are Khalas, Chamada, Mungoth, and Krangath. Each layer is differentiated from the other by its degree of volcanic activity.

Gehenna has the following traits.

• Normal gravity. Gravity is similar to that of the Material Plane, but naturally occurring volcanic mountains seem to float free in an infinitely larger void. Gravity is normal on the steep slopes of a mountain, and a fall causes a creature to tumble until a chance ledge catches it, or until continued abrasions from the long fall completely shred the victim.
• Divinely morphic. Lesser deities can alter Gehenna’s mountainous landscape. Ordinary creatures find that Gehenna is as alterable as the Material Plane.
• Mildly evil-aligned.

Random Encounters: Use the Hellish Encounters table (page 167) for random encounters in Gehenna.

Example Gehenna Site: Valley of the Outcast

Mungoth, the third layer of Gehenna, is a cold place. The light of scattered volcanic vents is equivalent to that of a full moon, making navigation across the icy slopes difficult. Mungoth’s features are further masked by heavy precipitation, in the form of both snow and ash. That makes it a good place for those who don’t want to be found.

A deep chasm contains a well-hidden realm sheltered from the ever-present acidic snow. Built of equal parts basaltic rock and giant bones is a rough castle. The castle is scaled to the proportions of its master, an outcast fire giant wizard named Tastuo. Her eight siblings, fellow outcasts, also reside in the castle.

The fiends who rule Mungoth have several interlocking contracts with Tastuo, which helps ensure the valley’s safety should her enemies ever find her. Tastuo never names those enemies, but her predicament makes her sympathetic to the plight of travelers seeking asylum. Thus, the Valley of the Outcast doubles as a way station for visitors in need, but only if they can find it. And the fiends of Mungoth are always looking for intruders⁠—Tastuo’s protection doesn’t extend beyond her castle walls.

To draw an encounter map for the area near the Valley of the Outcast, use the guidelines for forbidding mountains. Then cover all surfaces with snow, deep snow, or ice as you see fit.

The snow-ash mixture on Mungoth deals 1d4 points of acid damage per minute of exposure. Only artificial structures or caverns offer any lasting protection against the snowfall, which blows through any given area 80% of the time.

Nine Hells of Baator

This plane, sometimes simply called Baator or Hell, is the ultimate realm of law and evil, the epitome of premeditated, crafted cruelty. The devils of the Nine Hells all obey a higher law than themselves, but all that really means is that they chafe and rebel against their status. Most will undertake any plot or action, no matter how foul, to advance themselves.

The Nine Hells compare well with any other lower plane in terms of sheer diversity of vileness. Devils are more cunning, more subtle, and more dangerous than other fiends⁠—or so say the devils. A demon revels in slavering, insane, evil power, but a devil always has an agenda, a plan of attack, and a carefully conceived plot for retribution if necessary.

Baator consists of nine layers, each lower than the next, like ledges stepping down into an ever-deeper pit. From top to bottom, they are Avernus, Dis, Minauros, Phlegethos, Stygia, Malbolge, Maladomini, Cania, and Nessus.

The Nine Hells have the following traits.

• Infinite size. Each layer extends outward infinitely, but the circumference of each inner ledge (which opens onto the Pit and the next lower layer) is finite.
• Divinely morphic. Entities of at least lesser deity status can alter the Nine Hells. Ordinary creatures find that the Nine Hells is as alterable as the Material Plane.
• No elemental or energy traits. Elemental and energy influences are balanced, except on the layer of Phlegethos (which has the fire-dominant trait). The layer of Cania is bitterly cold and has a special cold-dominant trait. Creatures there take 3d10 points of cold damage each round they’re away from shelter of some kind.
• Mildly law-aligned and mildly evil-aligned.

Random Encounters: Use the Hellish Encounters table (page 167) for random encounters in the Nine Hells.

Example Nine Hells Site: Bronze Citadel

This brutish, unimaginative city on Avernus covers dozens of square miles and features twelve concentric ring walls, each bristling with war machines. The city is filled with hundreds of thousands of lesser devils of all kinds bound for the Blood War.

Because Avernus is the likeliest beachhead for any massed demonic attack, fortifications are always being added to the Bronze Citadel. Work gangs of lesser devils constantly expand the city. The construction is so pervasive that bone scaffolding is as likely to be supporting a given wall as not.

To create an encounter map for the Bronze Citadel, start with the battlefield elements described in the Plains Terrain section. Then add walls, towers and gatehouses described in the Urban Features section (page 99), and augment both with magical features such as flaming surfaces (which deal damage as a wall of fire spell), self-firing ballistas, and spikes that grow out of the walls (a trap triggered by the proximity of enemy troops).

Any kind of devil can be found here. Even a fight with low-level devils will quickly escalate, because the devil armies are disciplined enough to train their troops to report to their commanders that they’re under attack. Unless they employ stealth, characters will work their way up the food chain, eventually facing horned devils, ice devils, and pit fiends sent to find out what the commotion is.

Infernal Battlefield of Acheron

The hue and cry of battle is the first sound a soldier hears when arriving on Acheron and the last sound a refugee hears when leaving. That’s all Acheron offers: conflict, war, strife, and struggle. Many armies populate Acheron, but leaders are scarce. Truly, rebels without a cause are common on Acheron, whether they’re mortals, fiends, or celestials.

Avalas, Thuldanin, Tintibulus, and Ocanthus are the layers of Acheron, each made of island- or even continent-sized iron cubes floating in an airy void. Sometimes the cubes collide, and echoes of past collisions linger throughout the plane, mingling with the ring of sword on sword as armies clash across the faces of the cubes.

Acheron has the following traits.

• Objective directional gravity. Which way is down depends on which face of a cube you’re on. Walking across edges between faces can be dizzying for the inexperienced.
• Divinely morphic. Acheron changes at the whim of its deities. Ordinary creatures must use spells and physical effort to change the infernal battlefield.
• Mildly law-aligned.

Random Encounters: Use the Hellish Encounters table (page 167) for random encounters on Acheron.

Example Acheron Site: Thuldanin’s War-Cubes

The cubes of this layer are riddled with pockets and hollows. Surface pits lead down into labyrinthine spaces cluttered with the refuse of every war that was ever fought here.

Broken scraps of a myriad of devices are everywhere. Great ships that have burst asunder, toppled siege towers, enormous weapons, steam-driven carriages, flying devices of every description, and contraptions with even more obscure sources of power and purpose can be found within these cubes. Most of the refuse is inoperative, petrified to stonelike immobility by the “preservative” quality of the layer.

Scavenging for intact weapons is an occupation for many a team of salvagers and opportunists, because many quality weapons and engines of war are scattered through the rubble on Thuldanin.

But wise salvagers don’t spend too long on Thuldanin, because creatures can be petrified just as objects can be. Any given object or creature has a 1% cumulative chance per 30 days spent on Thuldanin of spontaneously petrifying into stone. Objects or creatures petrified by the natural qualities of Thuldanin cannot be returned to their previous state, except by such high-level magic as a wish or miracle spell.

To make encounter maps for the war-cubes, simply create expansive dungeon terrain: large rooms, wide hallways, tall ceilings, and so forth. Then fill much of it with junk (light rubble or dense rubble). Add large structures such as catapults, war galleys, and strange clockwork devices. Finally, add a few statues—unfortunate ex-adventurers who lingered too long looking for treasure.

Characters searching for treasure will undoubtedly confront rival salvagers; Thuldanin is known throughout the Great Wheel, so almost anyone or anything can be searching the caverns of the war-cubes. Not everything in Thuldanin is ruined. Constructs such as inevitables and golems might yet be functional, springing to action when the characters draw near. To represent the riches of the war-cubes, consider all creatures encountered here (except the constructs) to have double standard treasure. But rather than putting the treasure with the creatures, hide it among the debris of war and let the characters find the loot.

Clockwork Nirvana of Mechanus

Mechanus is the plane where perfectly regimented order reigns supreme. It consists of equal measures of light and dark, and equal proportions of heat and cold. On Mechanus, all law is reflected in a single infinite realm of immense clockwork gears, all interlocked, all turning according to their own measure. The cogs seem to be engaged in a calculation so vast that no deity knows its purpose, except that it is somehow a function of law.

At first glance, the nature of Mechanus seems straightforward. However, subtleties lurk just below the surface. Every kind of law can be found in the Clockwork Nirvana of Mechanus, from simple maxims to devilishly twisted rules of decorum.

Mechanus has the following traits.

• Objective directional gravity. The direction of “down” is oriented to the face of each rotating cog. Walking between cogs can be dizzying for newcomers⁠—and dangerous if a traveler falls between the cogs.
• Divinely morphic. Lesser deities can alter Mechanus with a thought; ordinary creatures require spells and physical effort to do so.
• Strongly law-aligned.

Random Encounters: Alternate between the Hellish Encounters table and the Heavenly Encounters table (page 167) for random encounters in Mechanus.

Example Mechanus Site: Fortress of Disciplined Enlightenment

This structure sits on its own cog, and its spires and towers rise high into the void of Mechanus. The fortress is 2 miles in diameter, and some of its spires reach twice that height. Inevitables enforcing the “don’t trespass” law patrol the parapets, keeping a vigilant eye out for fiendish infiltrators or colonizing formians.

A group of mortals from the Material Plane called the Fraternity of Order are the masters of the fortress. The members of the Fraternity of Order believe that if they can but tease forth every law of the cosmos, they will have the power of the deities. To that end, they built this stronghold on the plane of ultimate law.

A horde of clerks, functionaries, legal aides, translators, mathematicians, philosophers, and bureaucrats staff the Fortress of Disciplined Enlightenment. Most belong to the Fraternity of Order, though sometimes visitors are granted access to study at the vaunted libraries of the Fortress. The libraries extend through hundreds of rooms and hold tomes of legal volumes from all over the Great Wheel.

Characters seeking knowledge at the Fortress are never turned away outright, although a blizzard of paperwork must be negotiated before the fraternity allows access to the library’s general stacks. To study rarer, restricted tomes, characters must first complete a quest for the Fraternity. A typical mission would be to rescue a bit of abstract lore from a well-guarded drow library.

Peaceable Kingdoms of Arcadia

Arcadia thrives with orchards of perfectly lined trees, rulerstraight streams, orderly fields, and cities laid out in geometrically pleasing shapes. The mountains are unblemished by erosion. Everything on Arcadia works toward the common good and a flawless form of existence. Here, nothing intrudes on harmony.

It is said that everything on Arcadia is as perfect as it can be, neither as strictly regimented as Mechanus nor as devoted to the perfection of the individual as Celestia. But this is not entirely accurate. In fact, the inhabitants of Arcadia are often so convinced of their own righteousness that they are hard-pressed to recognize their own flaws.

Arcadia has two layers: Buxenus and Abellio. They look similar, except that Buxenus holds the armed camps of the celestial dwarves and archons that protect the plane.

Arcadia has the following traits.

• Divinely morphic. Lesser deities can transform Arcadia with a wave of the hand, but the plane has the alterable morphic trait for other creatures.
• Mildly law-aligned.

Random Encounters: Use the Heavenly Encounters table (page 167) for random encounters in Arcadia.

Example Arcadia Site: Mount Clangeddin

A perfectly conical mountain, standing apart from any range, rises at least thirty thousand feet above the fields below, its peak wreathed in clouds and storms. The great dwarf hero Clangeddin Silverbeard raised this edifice.

The mountain’s interiors are riddled with great halls, galleries, and dwarf-carved roads paved with flagstones. Costly lamps, hot and cold forges, and citywide feasting halls all provide light and merriment for the underground visitor. Strangers are welcome here, especially those who come to order special weapons from the legendary smiths who labor in the hottest portions of the forge.

The celestial dwarves who live within Mount Clangeddin spend half of each day drilling, training, and perfecting their military skills to honor their lord Clangeddin. Visitors seeking to raise an army sometimes come to Mount Clangeddin, tempting the dwarves with stories of righteous warfare. Sometimes, the elders are moved by such appeals and assign axes to the cause.

Others come seeking the legendary weapons that bear the mark of Clangeddin’s smiths. Though Mount Clangeddin is only a small city, weapons of any price can be bought (but not sold) here.

To draw an encounter map for Mount Clangeddin, use the Dungeon Terrain section (page 59). Because the dwarves take their stonecraft seriously, the walls, ceiling, and floors are the highest quality masonry and flagstone.

Seven Mounting Heavens of Celestia

The single sacred mountain of Celestia rises from an infinite sea of holy water to incomprehensible heights. Here, justice, kindness, order, celestial grace, and mercy are the rules. Here, watchful eyes hold the ramparts against evil in all its many forms. Here, all things are beautiful.

The Seven Mounting Heavens are the planar home for mortal souls who feel kindness and empathy for their fellow creatures. But it is a paradise that fiends of the lower planes would conquer if they could. Mount Celestia represents a promise of betterment and ultimate union with the powers of good and law for those worthy. So supplicants of every stripe ascend the layers, one after the other, to the ultimate height of the Heavenly City (the sixth layer), and from there into the Illuminated Heaven, about which nothing is known.

Celestia has the following traits.

• Divinely morphic. Celestia is morphic for entities of at least lesser deity status. It is alterable in the normal manner for more ordinary creatures.
• Mildly good-aligned and mildly law-aligned.

Random Encounters: Use the Heavenly Encounters table (page 167) for random encounters on Celestia.

Example Celestia Site: Empyrea

Also called the City of Tempered Souls, Empyrea sits on the edge of a cold, clear mountain lake. The many healing fountains and curative waters in Empyrea can restore withered limbs, lost speech, derangement, and life energy itself; those who ail need only find the right fountain. Empyrea is also known for its healers and hospitals, and many a pilgrim seeks to reach this legendary site of perfect health.

Nonevil, nonchaotic characters who seek relatively simple cures (damage, disease, or negative levels, for example) are freely healed. Those seeking cures for more exotic ills (strange curses, lost levels, and some rare, vile diseases) must pass the test of Empyrea—ritual combat against an archon or angel with a CR equal to the character’s level. If multiple PCs are fighting, they each get an archon or angel to fight. The fight is not to the death, but to unconsciousness⁠—and in fact those who kill their foes outright are banished from Empyrea. Those who pass the test are granted the cure they desire.

The fight takes place in one of many courtyards, an open area with slender, decorative pillars and shallow pools of purest water.

Twin Paradises of Bytopia

Bytopia is unique among the Outer Planes because the surfaces of its two layers face each other like the covers of a closed book. By looking up from Dothion, the “top” layer of the plane, the traveler can see Shurrock, its other layer. In similar fashion, one may stand on Shurrock and see the towns and farms of Dothion overhead.

Each layer of Bytopia plane is an idealized world. Dothion is a tamed, pastoral landscape, while Shurrock is an untamed wilderness. The philosophy of the plane⁠—personal achievement working with social interdependence—infuses both its layers.

The distance between the two layers of the plane is about 1 mile, though sharp mountains rise from either side and sometimes meet in the middle. Travel between the two layers is common by flying as well as climbing the mountains.

Bytopia has the following traits.

• Objective directional gravity. “Down” exists in opposite directions on the plane’s two facing layers. Gravity is normal until one crosses the invisible border between the two layers; then it reverses. Those who break through the border find themselves falling toward the other plane.
• Divinely morphic. Lesser deities can transform Bytopia’s twin landscapes, and other creatures find Bytopia as changeable as other Outer Planes.
• Mildly good-aligned.

Random Encounters: Use the Heavenly Encounters table (page 167) for random encounters on Bytopia.

Example Bytopia Site: Mottlegrasp’s Orchard

Mottlegrasp, an 18th-level celestial gnome wizard, tends an orchard in rural Dothion where the trees grow rubies, emeralds, and other precious gems. A typical tree produces 1d4×1,000 gp worth of gems each year, and the orchard covers several acres.

Some of Mottlegrasp’s trees provide far more valuable fruit. He can offer fruit of Strength, Dexterity, Constitution, Intelligence, Wisdom, and Charisma. These objects function as the relevant ability-enhancing tomes and manuals (described in Chapter 7), providing an inherent bonus to an ability score when eaten. The riper the fruit, the higher the bonus.

Neither money, good deeds, nor fame will earn the PCs such fruit. Mottlegrasp never parts with his fruit willingly, and he politely turns down any offers to do so⁠—with one exception: Mottlegrasp will occasionally pay characters in fruit if they guard his orchard for a week’s time.

The venerable gnome is no fool. He will hire guards for his orchard only if he suspects a threat will emerge that an 18th-level wizard on his home turf can’t handle. The characters will likely face peril after peril during their week as orchard-guards.

To draw an encounter map of Mottlegrasp’s Orchard, place trees in neat rows of every other square. Every four rows or so, draw an irrigation canal (treat as a 5-foot-wide trench, because it’s rarely full of water).

Blessed Fields of Elysium

Elysium is the most strongly good-aligned plane on the Great Wheel, a place of good untrammeled by issues of law or chaos. On this plane, doing well by others is more highly valued than any other ideal.

The first layer of the plane, Amoria, is a riot of color. Visitors marvel at brilliant green meadows dotted with starburst flowers, pools as deep blue as a jay’s plumage, and silver clouds drifting against a perfect sky. The plane itself seems to vibrate with its own sense of life and intensity. It is usually a peaceful place, and tranquility seems to seep into the bones and souls of those that cross it.

Elysium consists of four layers strung together by the myriad courses of the River Oceanus. The first layer is most like the Material Plane, with sweet-smelling pines and flowering trees along its banks giving way to open meadows and rolling fields. The second layer, Eronia, is rougher and more mountainous, and rapids and falls are common along the channels of the river. Belierin, the third layer, is a great marsh awash with life. The deepest layer is the sea of Thasasia and the headwaters of the great River Oceanus, dotted with islands where veteran heroes of good relax for eternity.

The size of the River Oceanus varies from a braid of smaller side channels to a mighty flow that tops its banks and floods the surrounding area. Along the river are islands, low gravel bars, and rocky promontories, which are often the homes of honored souls of the dead and more powerful denizens.

Elysium has the following traits.

• Divinely morphic. Elysium is easily altered by deities. Other creatures find that their spells and physical efforts work normally here.
• Minor positive-dominant.
• Strongly good-aligned.
• Entrapping. This is a trait unique to Elysium (although Hades has a similar entrapping trait). A nonoutsider on Elysium experiences increasing joy and satisfaction while there. Colors become brighter and more vivid than on the Material Plane, sounds more melodious and soft, and the nature of others seems more pleasant and understanding. At the conclusion of every week spent on Elysium, any nonoutsider must make a Will save (DC 10 + the number of consecutive weeks on Elysium). Failure indicates that the individual has fallen under the control of the plane, cannot leave the plane of his or her own volition, and has no desire to do so. Memories of any previous life fade into nothingness, and it takes a wish or miracle spell to return such characters to normal.

Random Encounters: Alternate between the Heavenly Encounters table and the Beatific Encounters table (page 167) for random encounters in Elysium.

Example Elysium Site: Heroic Isles

These islands are also known as the Isles of the Holy Dead, the Hills of Avalon, and the Islands beyond the World. Here the best of the good-aligned souls who have passed beyond the mortal world make their homes, retaining some knowledge and perhaps some power from their previous lives. Here hero-kings wait for the day when their nations need them again, and religious scholars research great mysteries in huge libraries.

Often these great petitioners made the journey to Thalasia while still alive but approaching death, whether from age or from wounds taken in noble battle. Elysium then slowly converted them to powerful outsiders, and they scarcely felt the pang of death. In Thalasia they retain their powers and memories but are at peace with themselves and with others, the ultimate reward for good. Angels guard the shores of each island, observing visitors silently and ruthlessly swarming any who would break the peace of this place.

Because the dead heroes remember their mortal deeds, they can be sources of information and inspiration for the PCs. Some may have unfinished business on the Material Plane and charge the characters with righting some long-ago wrong.

The characters may seek out the Heroic Isles as part of an adventure that takes place elsewhere. When the Prophecy of the Moon Asunder must again be forestalled, it’s useful to get advice from the paladin who forestalled it a thousand years ago.

Wilderness of the Beastlands

The Wilderness of the Beastlands is a plane of nature unbound. It is a plane of forests, ranging from mangroves hung heavy with moss to snowfall-laden pines to acres of sequoias so thick that no light penetrates their canopy. Oak, birches, spruces, firs, and maples are common here, and explorers into the plane’s distant corners find great forests of giant fungi and mushrooms. Vast deserts are found here as well, though they are hardly barren wastelands. Cactus, aloe, and other desert plants thrive in the arid parts of the Beastlands.

The air of the Beastlands is ideal for anything that grows. It is humid and warm in the swampy regions, calm and cool beneath the sequoias, breezy and clear among the beeches, and arid and hot in the more open lands.

The Beastlands consists of three layers, each layer frozen at certain parts of the day. The top layer, Krigala, is a place of eternal daylight; Brux is a domain of perpetual twilight; and the third layer, Karasuthra, is a land of night illuminated only by a pale moon.

The most important aspect of the Beastlands is how the plane favors animals of all kinds. Like Arcadia, it is a plane heavily populated by animals and magical beasts. Traditional towns, cities, and strongholds are few and far between. Those who make their homes here seek to live with the trees, not against them.

The Beastlands has the following traits.

• Divinely morphic. Deities can shape the plane’s traits with a thought, but mortal creatures must use spells or physical effort to affect a change in the plane.
• Mildly good-aligned.

Random Encounters: Use the Beatific Encounters table (page 167) for random encounters in the Beastlands.

Example Beastlands Site: Karasuthra Hunter’s Glen

The lowest layer of the Beastlands, Karasuthra wears a cloak of continual night. A silver moon whose phases change slowly hangs in the open sky, surrounded by stars that lazily drift across the sky. Only a few beacons of moonlight piece the thick canopy of the forest here, forming silver shafts that touch the forest floor.

Karasuthra is the home of the most dangerous night creatures, predators relentless in the pursuit of their quarry. Hunters from the Material Plane sometimes journey to Karasuthra looking for the most dangerous of trophies. Some survive to try a second time.

Among the most famous game in the place are the white stags. These elusive creatures (treat as celestial chargers) live for the thrill of the chase and consider the hunt part of their life cycle. Even the most devoted defender of good can hunt a white stag, for the stag knows the consequences and is willing to be prey. But white stags don’t give themselves up. They take great glee in using their wiles and unparalleled knowledge of the forest to confound hunters from other planes. No creatures native to the Beastlands will attack a white stag. Instead, they turn on the hunters with unbridled ferocity.

The antlers of a white stag stretch wide enough that it’s possible to fashion a composite longbow out of them using the Craft (bowmaking) skill (making checks against DC 30). Such a bow is considered of masterwork quality, and magical enhancements placed on the bow cost 10% less because the antlers have an affinity for magic.

To draw an encounter map for a Karasuthra hunter’s glen, use the medium forest guidelines. Simple three- and four-room lodges scattered throughout the forest offer visitors a measure of protection from the creatures outside.

Olympian Glades of Arborea

Arborea is a crazy quilt of climates and environments, all of which thrive. The plane contains great woods of towering maples, birch, and oak. These great deciduous trees strain skyward, leaving a forest floor relatively free of undergrowth and brush. The ground beneath the canopy itself is a rolling landscape of velvet moss and ferns. The forestscape sometimes retreats before open glades of wildflowers, fields of swaying wheat and barley, and neat rows of fruit trees untended by any hand. Here are trees that have never seen the woodsman’s axe, fields rich with grain, and orchards heavy with fruit.

The very air of Arborea seems charged with anticipation and excitement. Sudden squalls brew up out of nowhere, beating the tree-lined paths with heavy winds. They pass within minutes and leave behind warm, sunny arcs of light filtering through the forest canopy. In the distance there always seems to be music; sometimes the elves and the fey are playing, but just as often the faint tune is merely the wind curling through the boles of the great trees.

Arborea is a place with flowers in bloom and trees bearing fruit simultaneously. The uplands are covered with snow, shining beneath a crystal-blue sky. Arborea is almost overwhelming in its beauty, and the land embodies both wilderness and loveliness in one package.

Only the top layer of Arborea, Arvandor, has the great forest implied in the name of the plane. Aquallor, Arborea’s second layer, is an endless ocean, and its third layer, Mithardir, is a borderless desert of white dust.

Arborea has the following traits.

• Divinely morphic. Deities can change the traits of the plane and remake the landscape; mortals must use spells and physical effort to change their environment.
• Mildly good-aligned and mildly chaos-aligned.

Random Encounters: Use the Beatific Encounters table (page 167) for random encounters in Arborea.

Example Arborea Site: Canopy City

The celestial elves of Arvandor live in great treehouse cities among massive redwoods. There they hunt, celebrate, and live the idealized elven life. But they treasure their society with such intensity that they’re quick to turn on intruders. A single careless word can turn the speaker into a pincushion of elven arrows.

The canopy cities are not home to elves alone. Many elves ride celestial giant owls from place to place, and many fey are welcome in the treetop city. While the trees support the city, some treants live in the canopy city as well—a surprise to visitors who try to take a shortcut. A canopy city is considered a large city (see page 137).

To draw an encounter map for a canopy city, use the buildings from the Urban Features section (see page 99), but construct them of wood and attach them to tree trunks from 30 feet to 60 feet in diameter. Rather than use roads and alleys to connect them, string together rope bridges, wooden bridges, ladders, and stairs. Make the bridge-and-stairs network complicated⁠—the elves like it that way, and it’ll make for more interesting encounters.

Concordant Domain of the Outlands

The Outlands is unique among the Outer Planes because it borders all other Outer Planes. As a result, it is the common ground for extraplanar creatures. Beings from infernal and celestial planes, as well as those of law and chaos, can be found here. In addition, deities of true neutrality and those associated with ideals such as scholarship or nature have their realms here.

The Outlands is an infinitely large wheel with a great spire rising from its center. Outlanders consider this towering cylindrical plinth as the heart of the Outer Planes and the axle around which the Great Wheel is centered. This great plinth is clearly visible from anywhere in the plane; it rises above the clouds themselves and ascends into unreachable heavens. Sigil, the City of Doors, floats at the top of the spire.

The plane is a broad region of varied terrain, with open prairies, towering mountains, and twisting, shallow rivers. Settlements throughout the area are inhabited by a variety of refugees and natives of the plane. But they are small flecks against the greater wildness of the Outlands.

The Outlands has the following traits.

• Divinely morphic. This trait disappears close to the center of the plane, and in that area even deities are affected by the nature of the plane.
• Mildly neutral-aligned. Unlike on the other Outer Planes, all alignments are equally welcome on the Outlands.
• Normal magic, impeded magic, and limited magic. The Outlands has the normal magic trait far from its central spire, but as one approaches the hub of the plane, spells, spell-like abilities, and even supernatural powers are further and further restricted. Where the surface of the plinth is near vertical, almost no abilities (and few deity-level powers) function.

Far from the spire, magic functions normally. At about 1,100 miles from the base of the spire, the impeded magic trait begins, impeding 9th-level spells unless the caster succeeds on a DC 35 Spellcraft check. Closer to the base of the spire, spells of lower levels are also impeded in this manner, according to the table below.

The limited magic trait starts to emerge at 900 miles away from the center of the plane, making 9th-level spells and spell-like effects unavailable. Closer to the center, more and more abilities cannot be used, and finally even deity-level powers are affected. Extraordinary abilities are never affected by this trait.

Random Encounters: Alternate among all four random Outer Plane tables for random encounters in the Outlands.

Example Outlands Site: City of Sigil

The heart of the Outlands, and therefore the self-proclaimed center of the planes, Sigil is known as the City of Doors. Portals leading throughout the cosmos lace every district of the city. Situated atop the spire itself that rises above the surrounding plane, Sigil is a ring floating in space, with the city itself constructed along the inside of the band.

Sigil has a number of special traits, one of which is objective directional gravity. “Down” is toward the ring itself. Those who escape the ring suddenly find themselves in open air, often plummeting down the side of the spire.

While magic is extremely limited near the spire, the City of Sigil has the normal magic trait. Sigil has a huge number of portals, the sum total of which is unknown even to the inhabitants. Portals connect to every known Outer Plane and every Inner Plane. Portals also connect Sigil to other locations in the Outlands. Most of Sigil’s portals require command words or special keys in order to make them function.

Sigil is a trader’s city. Goods, merchandise, and information come to it from across the planes. It does a brisk trade in information about the planes, in particular in the command words or keys required for the operation of particular portals. These portal keys are sought after, and usually travelers within the city are looking for a particular portal or a portal key to allow them to continue on their way.

Sigil is controlled by a number of factions, all of which may be politely described as “philosophers with clubs.” These factions are categorized along the lines of traditional alignments, and they control different parts of the city and different services therein. The ultimate ruler of Sigil is an enigmatic being known as the Lady of Pain, a floating female humanoid with bladelike hair. The full extent of the Lady of Pain’s abilities is unknown, but it is widely assumed that her power equals or exceeds that of the deities.

Sigil is huge⁠—ten times the size of a Material Plane metropolis. Accordingly, no gp limit applies when buying or selling goods in the City of Doors, and NPCs of any class and level combination can be found there.

To draw an encounter map for Sigil, start with a normal cityscape and add as much magic to the environment as you can. Entertaining illusions, animated “horseless carriages,” buildings built from walls of force⁠—anything you can imagine probably exists in Sigil somewhere.

Random Outer Plane Encounters

On this page are four alignment-based random encounter tables that you can use if the PCs find themselves on one of the Outer Planes unexpectedly. If you’re writing an adventure that takes place on a particular Outer Plane, you can use these encounter tables as a starting point, designing specific tables that reflect the nature of the adventure site and the level of the PCs.

Creating a Cosmology

As you build your world, you’ll eventually move onto other worlds entirely⁠—​new planes where anything is possible. And if you’re ambitious, you can create your own cosmology.

What Planes Do You Need?

The cosmology you create should fit the needs of your campaign. Assuming that the Material Plane of your campaign is essentially the same as the Material Plane of the D&D cosmology, you need to decide what your cosmology will contribute to the campaign. Here’s a list of features that a “typical” D&D campaign needs a cosmology to provide:

• A place for deities to reside or originate from.
• A place for fiendish creatures to originate from.
• A place for celestial creatures to originate from.
• A place for elemental creatures to originate from.
• A way of getting from one plane to another.
• A way for spells that use the Astral Plane, the Ethereal Plane, or the Plane of Shadow to function.

None of these are an absolute requirement for your campaign. You can run a campaign without deities at all, or with deities that are unreachable or that don’t have extraplanar kingdoms. You can decide that fiendish and celestial creatures come from the same plane, or that all elementals come from the same swirling maelstrom. You may decide that you don’t want to have any of the Transitive Planes in your campaign.

Your cosmology can reflect your own desires for the direction you want the campaign to take. If you want to stress the struggle between good and evil, then setting up strongly aligned planes for these concepts is an excellent idea. Similarly, if you want a strong conflict between organization and freedom, strongly law-aligned and strongly chaos-aligned planes are recommended. You can create, add, and subtract planes as you see fit. If you want a fifth elemental plane (perhaps elemental cold, elemental wood, or even elemental emptiness), you can do so within your cosmology.

Planar Traits

Designing a plane is like designing any other landscape⁠—although most planes are more fantastic and strange than the forests, mountains, and plains that dominate the Material Plane. You might include exotic terrain, vast dungeons, mighty fortresses, or cities teeming with weird denizens. In addition to these elements, you’ll want to establish planar traits: rules that define how a plane works in general terms.

The planes of D&D’s Great Wheel cosmology each have planar traits that explain how characters move, fight, and cast spells there. The Elemental Plane of Fire, for example, has the fire-dominant trait, which means that the very substance of the plane deals 3d10 points of fire damage every round to creatures present on the plane. The Astral Plane has the subjective directional gravity trait, so creatures on the plane decide for themselves which way they would like gravity to pull. Limbo has the strongly chaos-aligned trait, so nonchaotic characters are penalized there.

When you design a plane for your own cosmology, choose the traits described for planes on the Great Wheel (pages 147–150) or invent your own. You can mix and match the traits from different planes if you like. For example, you could create a plane called the Forge of Heaven that was both fire-dominant and good-aligned.

Planar traits usually apply to the plane as a whole, but a plane is a vast place. There may be particular locations within a plane where the rules are different, perhaps because of natural effects, godly interference, or magical localities.

A plane usually has traits that describe its gravity, the nature of time on it, its size and shape, its morphic nature (how easy it is to change reality there), its alignment, its elemental or energy type, and any unusual effects on magic that occur on the plane. That’s not an exhaustive list, however⁠—design whatever planar traits you need to make a plane you create work the way you want it to.

Additional Traits

Here are some planar traits that aren’t used in the D&D cosmology but that might make good building blocks for planes you design.

Light Gravity: The gravity on a plane with this trait is less intense than on the Material Plane. As a result, creatures find that they can lift more, but their movements tend to be ungainly. Characters on a plane with the light gravity trait take a –⁠2 circumstance penalty on attack rolls and Balance, Ride, Swim, and Tumble checks. All items weigh half as much. Weapon ranges double, and characters gain a +2 circumstance bonus on Climb and Jump checks.

Strength and Dexterity don’t change as a result of light gravity, but what you can do with such scores does change. These advantages apply to travelers from other planes as well as natives.

Falling characters on a light gravity plane take 1d4 points of damage for each 10 feet of the fall (maximum 20d4).

You can choose to decrease gravity even further, doubling or tripling the effect for a particular plane.

Flowing Time: On some planes, time can flow faster or slower. One may travel to another plane, spend a year there, then return to the Material Plane to find that only six seconds have elapsed. Everything on the plane returned to is only a few seconds older. But for that traveler and the items, spells, and effects working on him, that year away was entirely real.

When designating how time works on planes with flowing time, put the Material Plane’s flow of time first, followed by the same flow in the other plane. For the example above, it would be 1 round = 1 year. For every year on the other plane, one 6-second round has elapsed on the Material Plane.

The clever and the unscrupulous can abuse planes that have flowing time. The ability to step into a slower time flow for the purpose of healing and regaining spells is an effective weapon against others. You’ll be back, completely refreshed, before your foes even know you’re gone. Throwing opponents into a plane with a slower time flow may keep them out of action for several years and make their return a problem for future generations.

Erratic Time: Some planes have time that slows down and speeds up, so an individual may lose or gain time as he moves between the two planes. For each plane with erratic time you create, develop a random generation table to determine the rate of time’s flow. The following is provided as an example.

You’ll want to set how often (by Material Plane standards) a plane with the erratic time trait shifts, requiring a new roll of the dice. To the denizens of such a plane, time flows naturally and the shift is unnoticed.

If a plane is timeless with respect to magic, any spell cast with a noninstantaneous duration is permanent until dispelled.

Finite Shape: A plane with this trait has defined edges or borders. These borders may adjoin other planes or hard, finite borders such as the edge of the world or a great wall. Demiplanes are often finite.

Self-Contained Shape: On planes with this trait, the borders wrap in on themselves, depositing the traveler on the other side of the map. A spherical plane is an example of a self-contained, finite plane, but there can be cubes, toruses, and flat planes with magical edges that teleport the traveler to an opposite edge when he crosses them. Some demiplanes are self-contained.

Static: These planes are unchanging. Visitors cannot affect living residents of the plane, nor objects that the denizens possess. Any spells that would affect those on the plane have no effect unless the plane’s static trait is somehow removed or suppressed. Spells cast before entering a plane with the static trait remain in effect, however.

Even moving an unattended object within a static plane requires a DC 16 Strength check. Particularly heavy objects may be impossible to move.

Sentient: These planes are ones that respond to a single thought⁠—that of the plane itself. Travelers would find the plane’s landscape changing as a result of what the plane thought of the travelers, either becoming more or less hospitable depending on its reaction.

Alignment Traits: How a plane develops an alignment trait is a chicken-and-egg situation. Certain planes are predisposed to particular alignments, so creatures of those alignments tend to settle there. This makes the planes even more disposed to that alignment, and so on. That does not have to be true for “home of the deities” planes you create.

A strongly neutral-aligned plane would stand in opposition to all other moral and ethical principles: good, evil, law, and chaos. Such a plane may be more concerned with the balance of the alignments than with accommodating and accepting alternate points of view. In the same fashion as for other strongly aligned planes (see page 149), strongly neutral-aligned planes apply a –⁠2 circumstance penalty to Intelligence-, Wisdom-, or Charisma-based checks by any creature that isn’t neutral. The penalty is applied twice (once for law/chaos, and once for good/evil), so neutral good, neutral evil, lawful neutral, and chaotic neutral creatures take a –⁠2 penalty and lawful good, chaotic good, chaotic evil, and lawful evil creatures take a –⁠4 penalty.

Dead Magic: These planes have no magic at all. A plane with the dead magic trait functions in all respects like an antimagic field spell. Divination spells cannot detect subjects within a dead magic plane, nor can a spellcaster use teleport or another spell to move in or out. The only exception to the “no magic” rule is permanent planar portals, which still function normally.