Zardun, Banished by Bontu

When Zardun, Banished by Bontu enters the battlefield, you may sacrifice another zombie. If you do, return X zombie creatures from your graveyard to the battlefield, where X is the converted mana cost of the sacrificed creature.
Embalm {3}{w}{b} (Exile this card from your graveyard: Create a token that's a copy of it, except it is a white Zombie Cleric with no mana cost. Embalm only as a sorcery.