Ephira, Blackstar Necromaster

Indestructible, deathtouch
Whenever Ephira enters the battlefield or attacks, return all creature cards from graveyards to the battlefield under your control, then choose Zombie or Spirit. If you chose Zombie, those creatures lose all abilities and are black Zombies in addition to their other colors and types. If you chose Spirit, those creatures are 1/1 black Spirits in addition to their other colors and types.