| Hit Dice: | 10d10+30 (85 hp) |
| Initiative: | +5 |
| Speed: | 50 ft. (10 squares) |
| Armor Class: | 15 (–1 size, +1 Dex, +5 natural), touch 10, flat-footed 14 |
| Base Attack/Grapple: | +10/+18 |
| Attack: | Bite +13 melee (2d6+6) |
| Full Attack: | Bite +13 melee (2d6+6) |
| Space/Reach: | 10 ft./5 ft. |
| Special Attacks: | Improved grab, wrenching attack |
| Special Qualities: | Darkvision 60 ft., ethereal bite, low-light vision, scent, true sight |
| Saves: | Fort +10, Ref +8, Will +6 |
| Abilities: | Str 19, Dex 13, Con 17, Int 6, Wis 12, Cha 12 |
| Skills: | Jump +15, Listen +7, Spot +6, Survival +4; racial bonuses |
| Feats: | Alertness, Improved Initiative, Iron Will, Track |
| Environment: | Any cold or temperate land |
| Organization: | Solitary or pack (5–20) |
| Challenge Rating: | 8 |
| Treasure: | None |
| Alignment: | Usually neutral |
| Advancement: | 11–15 HD (Large); 16–30 HD (Huge) |
| Level Adjustment: | +6 |
Nethersight mastiffs are fierce predators native to arctic and subarctic areas of the Material Plane. These imposing, muscular canines have a taste for ethereal flesh, and they pursue it zealously, often passing over easier Material Plane prey in favor of a hunt on the Ethereal Plane.
A nethersight mastiff resembles a tremendous dire wolf with a black, shaggy coat and huge paws. It has a broad head with a short, wide muzzle, and its teeth glow with a pearly blue light. The typical nethersight mastiff is 8 feet in length and weighs 700 pounds.
Nethersight mastiffs speak Common.
Nethersight mastiffs are bold, aggressive carnivores that usually hunt in large packs, surrounding their prey to prevent escape, and then closing in for the kill. Because ethereal prey is more difficult to catch than Material Plane creatures, mastiffs always attack quickly and hold on with their jaws.
Improved Grab (Ex): If a nethersight mastiff hits an opponent that is at least one size category smaller than itself with a bite attack, it deals normal damage and attempts to start a grapple as a free action without provoking an attack of opportunity (grapple bonus +18). If it gets a hold on an ethereal creature, it can attempt a wrenching attack on the next round. Alternatively, the nethersight mastiff has the option to conduct the grapple normally, or simply use its jaws to hold the opponent (–20 penalty on grapple check, but the nethersight mastiff is not considered grappled). In either case, each successful grapple check it makes during successive rounds automatically deals bite damage.
Wrenching Attack (Su): A nethersight mastiff can wrench a grabbed ethereal opponent onto the Material Plane by making a successful grapple check (grapple bonus +18). A wrenched opponent is then trapped on the Material Plane unless it has the means to return to the Ethereal Plane.
Ethereal Bite (Su): A nethersight mastiff’s teeth have abilities similar to those of a ghost touch weapon, allowing it to bite ethereal creatures and negating the usual miss chance on any attack against an incorporeal creature.
True Sight (Su): This ability functions like the true seeing spell (caster level 16th), except that it is continuously active.
Skills: A nethersight mastiff receives a +5 racial bonus on Spot checks when hunting creatures that are on the Ethereal Plane.
Source: Monster Manual II, page 160. This creature’s statistics block has been updated to version 3.5 as given in the D&D® V.3.5 Accessory Update for Monster Manual II. Changed “True Seeing” special quality in the descriptive text to “True Sight” to match the text in the Special Qualities entry and to reduce confusion with the actual true seeing spell.