Akuma, Rising Serpent

Echolocation. Akuma can't use its blindsight while deafened. 

Feasting Cruelty. If Akuma hits a creature with a Tail attack and it is Grappled, Akuma can make one Bite attack against it as a Bonus Action.

Heated Body and Shrieking Rebuke.  A creature that touches Akuma takes 7 (2d6) fire damage. If a creature that can hear him hits Akuma with an attack while within 10 ft. of him, it takes 7 (3d4) psychic if he isn't Incapacitated.

Magic Weapons. Akuma’s weapon attacks are magical. 

Tail. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 10 (2d6 + 4) bludgeoning damage plus 7 (2d6) fire damage. If it is large or smaller. the target is Grappled escape DC 16. Until this grapple ends, the target is Restrained if it isn't large, Akuma can automatically hit the target with its tail, and Akuma can't make tail attacks against other targets.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 11 (2d8 + 4) piercing damage plus 7 (2d6) fire damage. If the target is a creature other than a Construct, it must succeed on a DC 16 Charisma saving throw or take 16 (3d10) psychic damage.

Phantom Claws. Akuma attacks one creature with phantasmal claws that is within 5 ft of it and can see it. The target must make a DC 16 Intelligence saving throw. On a failed save, the target takes 3d10 psychic damage and is frightened until the end of its next turn. A creature immune to illusions or with truesight automatically succeeds.