Baku Familiar

Shapechanger. The Baku can use its action to polymorph into a beast form that resembles a cat (speed 20 ft.), a butterfly (20 ft., fly 60 ft.), or a monkey (20 ft., climb 20 ft.), or back into its true form. Its statistics are the same in each form, except for the speed changes noted. Any equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies.

Eater of Nightmares. When the baku is subjected to a Wisdom saving throw against an effect that would cause it to become frightened, it instead heals hit points equivalent to the effect's DC or the damage, if any (whichever is higher). Each friendly creature within 30 feet of the baku has advantage on Wisdom saving throws against being frightened.

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

Fey Nature. The baku adds its Charisma modifier to its AC (included in the statistics).

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) piercing damage

Nightmare. Ranged Spell Attack: +6 to hit, range 60 ft., one target. Hit: 6 (1d4 + 3) psychic damage. On hit, the creature must succeed on a DC 11 Wisdom saving throw or drop whatever it is holding and become frightened until the baku's next turn.