Swarm of Bats

A swarm of Vampire Bats descends from the sky and attacks all other creatures in a 15 foot radius around you. When a creature enters the area for the first time on a turn or starts its turn there, it must make a Wisdom saving throw. On a failed save, the creature takes 4d4 piercing damage and becomes Frightened until the beginning of its next turn. On a successful save, the creature takes half as much damage and is not Frightened.

At Higher Levels: When you cast Swarm of Bats as a 4th level spell, you can maintain it for 5 minutes, it deals 2d4 additional piercing damage and the radius extends by an additional 5 ft. When cast as a 5th level spell, you can maintain it for 10 minutes, it deals 4d4 additional damage, its radius is extended by 10 ft. and you can you can designate any number of creatures you can see to be unaffected by it.