Wastrilith

Large Outsider (Aquatic, Cold, Chaotic, Evil)
Hit Dice:	15d8+30 (97 hp)
Initiative:	+2 (Dex)
Speed:	20 ft., swim 40 ft.
Armor Class:	21 (-1 size, +12 natural)
Base Attack/Grapple:	0
Attack:	0
Full Attack:	Bite +19 melee, 2 claws +14
Space/Reach:	5ft. by 5ft./10ft.
Special Attacks:	Spell-like abilities, breath weapon, water elemental control
Special Qualities:	Damage reduction 10/+1, lightning vulnerability, cold subtype, immunities, SR 16, tanar'ri qualities
Saves:	Fort +11, Ref +11, Will +11
Abilities:	Str 20, Dex 15, Con 15, Int 14, Wis 14, Cha 12
Skills:	Bluff +12 Concentration +17, Escape Artist +15, Hide +13, Knowledge (any two) +15, Listen +24, Move Silently +11, Search +13, Spellcraft +12, Spot +20
Feats:	Blind-Fight, Cleave, Expertise, Power Attack
Environment:	Any aquatic
Organization:	Solitary or troupe (1 wastrilith, 2-12 sharks, and
Challenge Rating:	13
Treasure:	Standard coins; double goods; standard items
Alignment:	Chaotic Evil
Advancement:	16-22 HD (Large); 23-45 HD (Huge)
Level Adjustment:	0

Wastrilith are horrendous looking creatures, appearing as long serpents covered in scales and with the addition of a pair of humanoid arms, each of which is tipped by three razor sharp claws. Their mouths are also filled with sharp needle-like teeth. Their eyes are a luminescent and contrast greatly with their dark scales.

For more information, see the Planescape Monstrous Compendium Appendix I (pg. 111).

CombatSpell-Like Abilities: At will : darkness, desecrate, detect good, teleport without error (self plus 50 pounds of objects only). Those abilities are as the spells cast by a 15th level sorcerer (DC 11 + spell level).Breath Weapon (Su): Cone of boiling water, 30 feet long, once every 1d4 rounds; damage 6d6, Reflex half DC 18.Water Elemental Control (Su): Water elementals do not attack wastriliths even if summoned. The water lord has a 50% chance of wrestling control of water elementals from the summoner up to 100 feet away.Lightning Vulnerability (Ex): Unlike other tanar’ri, the water lords take normal damage from lightning. However, due to their magical nature, half of these attacks are deflected back to the attacker.Cold Subtype (Ex): Cold immunity; double damage from fire except on a successful save.Immunities (Ex): Wastriliths are immune to water-based attacks and spell-effects.Habitat/SocietyWastrilith are extremely territorial, and once they have established their teritory, they never venture far from it, nor do they permit any other powerful creatures to establish a presence nearby. 0EcologyA wastrilith typically secures an area 25 miles in diameter to be its territory, and located at the centre of this territory is its lair. Whether that be a marvel of aquatic engineering, or just a hole in a coral reef depends on the individual creature.