Aphathis, Unending Terror

Horrors, Nightmares, Specters, and Shades get
+1/+1 and have persist.
Whenever a Horror, Nightmare, Specter, or
Shade enters the battlefield, each opponent exiles
a card from their hand. If they cant, they lose 3
life. You may play cards exiled this way and may
spend mana as though it were mana of any color
to cast them.
(* equals the number of cards in exile.)