Phiuhl (CR 11)
AC: 16 (-1 size, +5 Dex, +2 natural), touch 14, flat-footed 11
Hit Dice: 9d8+36 (76 hp); DR: 10/magic
Fort +7, Ref +8, Will +6
Speed: 40 ft., fly 30 ft. (perfect)
Space: 10 ft./10 ft.
Base Attack +6; Grapple +10
Attack: Heat touch +6 melee
Full Attack: 2 heat touches +6 melee
Damage: Heat touch 1d10 fire
Special Attacks/Actions: Death gas, desiccate, heat aura
Abilities: Str 11, Dex 20, Con 19, Int 10, Wis 11, Cha 10
Special Qualities: Acid immunity, electricity resistance 20, fire immunity, gaseous form, immunities, inscrutable mind, poison immunity, SR 21
Feats: Combat Reflexes; Dodge; Improved Initiative; Weapon Focus (heat touch)
Skills: Hide +9, Move Silently +13, and Spot +8
Advancement: 10-19 HD (Large); 20-27 HD (Huge)
Climate/Terrain: Any land and underground (Gehenna)
Organization: Solitary or pair
Death Gas (Ex): Any creature susceptible to poison within 50 feet of a phiuhl must succeed on a Fortitude save (DC 18) or take 1d10 points of Constitution damage immediately and another 1d10 points of Constitusrion damage 1 minute later (unless another DC 18 Fortitude save is made). Those who save against a phiuhl's death gas are immune to that phiuhl's gas for one day.
Desiccate (Ex): Any character in a square occupied by a phiuhl at the end of the phiuhl's turn must make a Fortitude save (DC 18) or gain two negative levels. The saving throw to remove one of these negative levels also has a DC of 18.
Heat Aura (Ex): Anyone within 30 feet of a phiuhl must make a successful Fortitude save (DC 18) or take 1d6 points of fire damage. Treat this effect as a burst that continually radiates from the creature.
Gaseous Form (Ex): A phiuhl's insubstantial form grants it immunity to critical hits. A phiuhl cannot run, but it can fly (slowly), and it is subject to winds. It cannot wear armor, manipulate solid objects, or enter water or other liquids. It can pass through small holes or narrow openings - even mere cracks. It also can occupy squares occupied by enemies (see Desiccate, above).
Inscrutable Mind (Ex): Any creature attempting to establish a telepathic link to a phiuhl's mind (via detect thoughts, psionic ability, dominate monster, and so on) must make a Will save (DC 14) or suffer the effects of feeblemind as cast by a 9th-level sorcerer.
A phiuhl knows it can't do much damage with its heat touch, so instead it prefers to fly above its enemies so that it can subject as many of them as possible to its death gas without risking melee. Thereafter, it swoops in for desiccating attacks until all its enemies have been destroyed.
A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.
Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.