Level: Sorcerer 5, Wizard 5
Components: V, S, M
Casting Time: 1 round
Range: Touch
Saving Throw: Fortitude negates
Spell Resistance: Yes
Your intended subject begins to grow rapidly as you complete the spell.
This spell causes instant growth of a humanoid creature, doubling its height and multiplying its weight by 8. This increase changes the creature’s size category to the next larger one. The target gains a +2 size bonus to Strength, a –2 size penalty to Dexterity (to a minimum of 1), and a –1 penalty on attack rolls and AC due to its increased size.
A humanoid creature whose size increases to Large has a space of 10 feet and a natural reach of 10 feet. This spell does not change the target’s speed.
If insufficient room is available for the desired growth, the creature attains the maximum possible size and may make a Strength check (using its increased Strength) to burst any enclosures in the process. If it fails, it is constrained without harm by the materials enclosing it—the spell cannot be used to crush a creature by increasing its size.
All equipment worn or carried by a creature is similarly enlarged by the spell. Melee and projectile weapons affected by this spell deal more damage (see Increasing Weapon Damage by Size). Other magical properties are not affected by this spell. Any enlarged item that leaves an enlarged creature’s possession (including a projectile or thrown weapon) instantly returns to its normal size. This means that thrown weapons deal their normal damage, and projectiles deal damage based on the size of the weapon that fired them. Magical properties of enlarged items are not increased by this spell—an enlarged +1 sword still has only a +1 enhancement bonus, a staff-sized wand is still only capable of its normal functions, a giant-sized potion merely requires a greater fluid intake to make its magical effects operate, and so on.
Multiple magical effects that increase size do not stack, which means (among other things) that you can’t use a second casting of this spell to further increase the size of a humanoid that’s still under the effect of the first casting.
Greater enlarge person counters and dispels greater reduce person.
Material Component: A pinch of powdered iron.
Source: Spell Compendium, page 82. The text is largely imported from enlarge person in the Player’s Handbook (version 3.5), page 226, and altered to account for the longer duration.