Hellmoon

{b}, Discard a card: Until end of turn, each creature card with morph or megamorph in your graveyard gains unearth. The unearth cost is equal to its morph cost or megamorph cost. (Pay the card's morph cost or megamorph cost: Return it to the battlefield. The creature gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)
"Yes, I've seen the netherworld. It was boring - much like a doctor's waiting room." - Liliana Vess