Dreadful echo

You whisper an ominous warning, and as you do other ominous voices join in one after the other. They must make a wisdom saving throw or take 5d8 psychic damage and causing fear for 3 rounds on a failed save, and taking half as much damage and not becoming afraid on a successful save. If used on a creature that is not engaged in combat they are incapacitated until the end of their next turn on a failed save instead.