Deathly Choir

Any target within X feet of the creature that isn’t protected by a mind blank spell hears in its mind the screams of the thousands of people the creature has killed. As a bonus action, the creature can force all targets that can hear the screams to make a Wisdom saving throw (DC = 8 + proficiency bonus + Charisma modifier). Each target takes Y psychic damage on a failed save, or half as much damage on a successful one. (Rahadin, pp. 237, CoS)