Mordekaiser, the exiled

Eminence — Whenever a permanent card would be exile from the battlefield or a graveyard, exile it with a realms of death counter on it.

You may play lands and cast spirit and zombie creature spells from among card in exile with a realms of death counter on them.

If Mordekaiser, the exiled would be exile, return it to the battlefield under its owner's control.

"Every soul shall serve."