Rokalos, the World-Ripper

+3: Create a 4/4 black Demon creature token with flying, trample and "When this creature deals damage, sacrifice it."
-X: Target player discards X cards, loses X life and exiles X cards from their graveyard. Create X colorless Skull artifact tokens.
-12: You get an emblem with "As long as you control Rokalos, your life total cannot be made lower than the number of Skull artifacts you control."