The Great Lord of the Dark

Undying
Whenever another nontoken creature you control leaves the field exile it, at the beginning of your
next upkeep return it to the battlefield under your control.
Eminence— As long as The Great Lord of the
Dark is in the command zone or on the battlefield, whenever a creature dies you may pay {b}{g}{4}, search your library for a creature care
with equal converted mana cost and put it into
your hand.