Avatar of Mammon

Acid Splash. When the troll takes damage of any type but psychic, each creature within 5 feet of the troll takes 9 (2d8) acid damage.

Regeneration. The avatar regains 20 hit points at the start of its turn. If the avatar takes radiant damage, this trait doesn’t function at the start of the avatar's next turn. The avatar dies only if it starts its turn with 0 hit points and doesn’t regenerate.

Magic Resistance. The avatar has advantage on saving throws against spells and magical effects. 

Multiattack. The avatar makes one Bite attack and one Constrict attack.

Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: 7 (1d6 + 4) piercing damage plus 4 (1d8) poison damage, and the target is poisoned until the start of the troll’s next turn.

Constrict. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage plus 9 (2d8) acid damage and the target is grappled (DC 15 escape).

Noxious Breath (Recharge 6). The avatar exhales a noxious cloud of poison and acid in a 30-foot cone. Each creature in the area must make a DC 16 Constitution saving throw. On a failed save, a creature takes 18 (4d8) acid damage and is poisoned for 1 minute. On a successful save, the creature takes half as much damage and isn’t poisoned. A poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.