Wind's Harp

False Appearance. While the wind's harp devil remains motionless, it is indistinguishable from an ordinary object.

Magic Resistance. The wind's harp devil has advantage on saving throws against spells and other magical effects.

Strong Winds. The wind's harp devil has advantage on attack rolls against a creature if at least one of its allies is an air elemental, wind demon, or similar creature of air, is within 20 feet of the target, and isn't incapacitated. rP

Multiattack. The wind's harp devil makes two infernal noise attacks.

Infernal Noise. Ranged Spell Attack: +6 to hit, range 60 ft., one target. Hit: 9 (2d8) psychic damage plus 3 (1d6) thunder damage.

Hellish Chorus (Recharge 5-6). The wind's harp devil creates an infernal cacophony. Each creature within 30 feet of it must make a DC 14 Dexterity saving throw, taking 13 (3d8) psychic damage and 7 (2d6) thunder damage on a failed save, or half as much damage on a successful one. Devils are immune to the hellish chorus.

Diabolical Countersong. When a spell is cast within 60 feet of it, the wind's harp devil plays a single, infernal note, interrupting the spell. This reaction works like the counterspell spell, except it only works on spells of 3rd level or lower.