Cetan

Slime Coat. This creature secretes a slime coating all over its body making it immune to nearly all types of poisoning and grappling attempts.

Tentacle Heads. The Cetan has two long tentacles protruding from its back that have their own mouths full of razor-sharp teeth and poison sacs.

Poison. This creature's teeth have a hollow cavity in them that contains poison. If a player is poisoned, they lose a certain amount of hit points at the beginning of each turn unless they are healed.

Slam. +7 to hit, reach 5 ft., 1 target. (2d8 + 7) bludgeoning damage. 

Slash. +5 to hit, reach 5 ft., 1 target. (1d8 + 5) slashing damage.

Bite. +7 (main head) +5 (tentacle heads) to hit, reach 5 ft. (main head), 10 ft. (tentacle heads) 1 target. (2d4 + (7 or 5)) piercing damage. When a successful attack is landed after this action, the target must make a Constitution Saving Throw (DC 15). If the target fails, they are poisoned and will take another (1d4 + 3) amount of poison damage.

Poison Tooth. Ranged Weapon Attack: +3 to hit, range 10/60 ft., 3 targets. (1d4 + 3) poison damage.When a successful attack is landed after this action, the target must make a Constitution Saving Throw (DC 15). If the target fails, they are poisoned and will take another (1d4 + 3) amount of poison damage.