Slave of Bolas

Threaten with a body count attached. The earlier generation of steal effects borrowed an opponent's creature for a turn, swung it back at them, and handed it back used; this design closes the loop by sacrificing the creature at the beginning of the next end step instead of returning it. Because the trigger fires on your own end step, the borrowed body never lingers to block on the opponent's turn: the window is exactly one combat phase, after which the creature is gone for good. The Grixis shard splits the labor that black's sacrifice and red's tempo both want: the untap-and-haste clause turns any target into an immediate attacker or activated-ability engine, and the forced sacrifice converts a one-turn loan into permanent removal that also nets you a swing of value. That dual nature carries the design; a straight steal effect only borrows, while this both removes and spends. It is a kill spell that happens to send the victim's own creature at them first, punishing an opponent for committing their best body to the board rather than letting you answer it cleanly on the stack. The five-mana sorcery-speed cost is the honest price for collapsing "remove their threat" and "use their threat against them" into one card; you pay in mana and in the inability to react at instant speed. The hybrid pip lets a deck lean toward red or blue, but the black is mandatory: at heart this is an aristocrats-adjacent piece of removal that asks you to spend an enemy's creature like a resource before it disappears.