Astral Chimare

Innate Spellcasting. The astral chimare innate spellcasting ability is Charisma (spell save DC 18, +8 to hit with spell attacks). She can innately cast the following spells, requiring no material components:

At will: detect magic, magic missile

2/day each: plane shift (self only), flame strike, sleep

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

Multiattack. The chimera makes three attacks: one with its bite, two with its claws. When its banishment breath is available, it can use the breath in place of its bite 

Bite. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 11 (6d6 + 8) radiant damage.

Claws. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit:  (4d8 + 12) slashing damage.

Etherealness. The Astral Chimera magically enters the Ethereal Plane from the Material Plane, or vice versa.

Banishment Breath (Recharge 5–6). The astral chimare exhales divine light in a 30-­-foot cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking (10d8) radiant damage on a failed save, or half as much damage on a successful one

All creatures that failed the saving throw must make a charisma DC 18 saving throw on a failed save the creature is banishment to Ethereal plane and can't return for a day

Undead, fiends and aberrations have disadvantage on this saving throw