Multiattack

The forest emperor makes two claw attacks and one tail attack. If both claws hit the same target, the target must succeed on a DC 18 Constitution saving throw or its hp maximum is reduced by 7 (2d6) and the forest emperor regains hp equal to this amount. This reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hp maximum to 0.

Acidic Claw

Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 16 (3d6 + 6) slashing damage plus 7 (2d6) acid damage.

Tail

Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 17 (2d10 + 6) bludgeoning damage.

Toxic Nectar Spray (Recharge 5-6)

The forest emperor sprays a 60-foot cone of acid from its flower-ringed eye pits. Creatures in the path of this cone must make a DC 18 Dexterity saving throw, taking 42 (12d6) acid damage on a failed save, or half as much damage on a successful one.