Chuul

Massive crustacean horrors bred to serve the aboleths. A chuul reeks of the deep and lunges from still water with claws spread wide — large enough to seize and crush a humanoid in one grip.

A chuul guarded the deep chamber at the back of the Tidefang's tidal sea cave, where five lizardfolk lay dead on the shore — crushed and bearing pus-filled nodules where the creature's poison had taken hold. It surfaced from a wide pool of black water and engaged the party in a single brutal exchange, seizing Vessel in one massive claw and crushing down. The party brought it low with lightning, fire, force-bolts, frost, thunder, and finally Vessel's blade through its skull.

Gryph recognized the chuul as a servant of the aboleth — a thrall bred to guard and to kill.