Large Elemental, neutral evil
Armor Class 15 (natural armor)
Hit Points 136 (16d10+48)
Speed swim +60, walk +30
Challenge 8
Skills perception +0
Damage Resistances acid, cold; nonmagic B/P/S attacks
Damage Immunities poison
Condition Immunities exhaustion, grappled, paralyzed, petrified, poisoned, prone, restrained, unconscious
Senses darkvision 60', passive Perception 10
Languages Aquan
Elemental Nature. Doesn't require air food drink or sleep.
Flammable Fumes. If it takes fire it erupts in a gout of flame. The weird immediately takes 5 (2d4) thunder and each creature within 10 ft. of the weird must make DC 15 Dex save or take 3 (1d6) thunder and 7 (2d6) fire.
Water Form. Can enter a hostile creature's space and stop there. It can move through a space as narrow as 1 inch wide with o squeezing.
Multiattack. Three Slam attacks.
Slam. Melee Weapon Attack: +7 to hit, 5 ft., one target, 13 (2d8+4) bludgeoning damage and the target must make DC 15 Con save or be poisoned until end of its next turn.
Sewer Overflow (Recharge 5-6). Emits a tide of filth and water from itself in a 15 ft. cube. Each creature in this cube: 18 (4d8) bludgeoning damage and 18 (4d8) poison and is infected with sewer plague (DC 15 Con half damage and isn't infected).
Source: Tome of Beasts 3 · OGL/Open