Amaymon

Encompass. After reaching half HP, Amaymon's form shifts to a pool of poison that spreads in a 50 feet radius from which Amaymon can attack and continuously deliver 1d4 poison damage each turn on a failed constitution save.

Poison Spray: 10-foot range. Amaymon projects a puff of noxious gas from its mouth. Target creature must succeed a constitution saving throw or take 3d12 poison damage.

 Poisonous Encasement: 5-foot range. Creature must roll a dexterity save or Amaymon pulls the creature into its body for 1d4+1 turns or until broken by a strength roll. The creature takes 1d4 poison damage, increasing by a d4 each turn the creature is encased.

Multiattack. Amaymon can make two melee attacks or one spell per turn.

Poison Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit:  8 (1d8 + 4) slashing damage and 4 (1d4 + 2) poison damage. Target must make a constitution save or be poisoned.

Poison Whip. Melee Weapon Attack: +4 to hit, reach 15 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage and the target must throw a strength save or be grappled. Until this grapple ends, the target is restrained. Each turn the target is restrained they must make a constitution save or take 4 (1d4 + 2) poison damage. Amaymon has two tentacles, each of which can grapple one target

Poison Thorn. Ranged Weapon Attack: +4 to hit, range 30/120 ft., one target. Hit: 6 (1d6 + 3) piercing damage and 4 (1d4 + 2) poison damage. Target must make a constitution save or be poisoned.

Poisonous Thorns. Amaymon is covered in poisonous thorns. When attacked with an open hand attack the attacker takes 1d4 piercing damage and 1d4 poison damage. If attacked with a close range weapon the attacker must make a dexterity save or take damage.