Banshee

You can summon a banshee any time during the day (even in sunlight) and she will attack your enemy during your round with her banshee wail. Any enemies within 40 feet must make a DC 10 Constitution saving throw. On a failure, enemy drops to zero. On a success, enemy takes 2d8 psychic damage. After her round, she disappears. 

(This spell is inspired by a spell of the same name in the game Wizard101)