The Unsacrificed King

Lifelink
When The Unsacrificed King enters the battlefield, return all cards from your graveyard to your hand.
{t}{x}: Gain control of {x} amount of creatures sacrificed in the last two turns. Unless it is a black creature, its power and toughness become 0/1.
Whenever a black creature you control enters your graveyard, you may pay {b}. If you do, return that creature to your hand.