Blurwing

Blurred Movement. Attack rolls against the blurwing have disadvantage unless the blurwing is incapacitated or restrained.

Evasion.  If the blurwing is subjected to an effect that allows it to make a Dexterity saving throw, it takes no damage.

Innate Spellcasting. The blurwing's spellcasting ability is Intelligence (spell save DC 11). It can innately cast the following spells, requiring no material components:

At will: gust, minor illusion, thunderclap 
1/day: color spray 

Magic Weapons. The blurwing's weapon attacks are magical.

Crowding.  The blurwing may occupy another creature's square.

Flock Tactics. The blurwing has advantage on attack rolls against a creature if at least one other blurwing is within 5 feet of the creature and the ally isn't incapacitated.

Tiny Rapier. Melee Weapon Attack: +9 to hit, reach 5 ft, one target.  Hit: 8 (1d1 + 7) piercing.

Dive Bomb. The blurwing uses its action to perform an aerial loop at terrifying speed. Each creature that can hear the blurwing must succeed on a DC 12 Wisdom saving throw or become frightened for one minute.  If a creature's saving throw is successful, or the effect ends for it, the creature is immune to any blurwing's Dive Bomb for the next 24 hours.

Missed Me (Recharge 5-6). The blurwing can vanish in response to impending harm.  Whenever it would take damage, it can instead use its reaction to take none.  The blurwing turns invisible, teleports to a space it can see up to 150 feet away, and remains invisible until the start of its next turn (or until it attacks or casts a spell).