Dagoth Ur, False Dreamer

Eminence — Whenever you cast an instant or sorcery spell from exile, if Dagoth Ur, False Dreamer is in the command zone or on the battlefield, that spell deals damage to target player equal to its mana cost.

{b/r}{u/r}: Target opponent mills 3 cards create a 2/2 black zombie for each creature card milled this way