The Shade Lord

Indestructible, Protection from multicolored
The Shade Lord can't be exiled.
Creatures you control are 4/3 black Shades in
addition to their other colors and types, and have,
"when this creature dies, return it to the
battlefield under its owners control at the
beginning of the next upkeep."
At the beginning of your first main phase,
sacrifice a Shade.
When The Shade Lord dies, you lose the game.