Illusive Master (5e Feat)

Prerequisites: Illusion spell
You have master the art of destroying the minds of your illusions victims. Any target you choose that is under the effects of your illusions takes 1d6 physic damage on each of their turns. Since they see the illusion as their bigger threat, they are unable to attack anyone else until they have seen through the illusion.

Gain an additional damage die at 5th level, 11th level, and 17th level.