unknowable beast

Unknowable. the unknowable beast when viewed causes a dc 20 wisdom save on a failed save the creature that viewed it cannot understand what they are looking at having disadvantage to hit or on a successful save the creature makes an additional wisdom saving throw dc15  on a success the creature takes 6d6 psychic damage or on a failed save taking 8d8 then making a third save dc15 or go mad and attack the nearest creature with a melee attack.

Multiattack. on its turn this creature makes 2 claw? attacks and either a fire or acid attack

Claw? Melee Weapon Attack: +8 to hit, reach 10 ft., 1 target. Hit:15  (3d6 + 6) [slashing] damage. 

Acid splash. RangedWeapon Attack: +4 to hit, range self/20 ft., 1 target. Hit: 12 (2d8 + 4) [acid] damage.

Fire spray. RangedWeapon Attack: +4 to hit, range self/20 ft., 1 target. Hit: 14 (2d8 + 6) [fire] damage.

as a bonus action before this creature attacks it can choose to frighten a creature that has looked at it dc16 wisdom save or be frightened. acts as concentration and can swap to a different creature forcing them to make a save at disadvantage.

absorb element. this creature (absorb elements) if it takes force, lightning, or cold damage giving it temp HP on top of the normal effect equal to half the damage taken. (requires line of sight)

the unknowable beast can use a legendary action after an action by a creature currently looking at it.

insanity (Costs 1/2 Actions). if the creature has disadvantage on attacking the unknowable beast it is now unable to move or cast spells for a round.