Heidezo, Death's King

Heidezo, Death's King enters the battlefield with
X 2/2 Black Zombies on the battlefield, where X is the number of creatures in your graveyard.
{w}{w}{u}{u} : Draw two cards and create two 1/1 White Spirit tokens with Flying.
{w}{u}{b}, Pay 2 Life: You may cast target creature card from your graveyard without paying for its mana cost.