Desecration Demon

Six power and flying for four mana is a body that should never have been legal at that rate, so the design pays for it with a Faustian bargain handed to the defending player: every combat, an opponent can trade a creature to keep this thing parked. The genius of the drawback is that it never costs the demon's controller anything directly. The tax is paid in your opponent's resources, and they choose whether to pay it. Against a grinding deck with chump fodder to spare, the demon idles, tapped down turn after turn while quietly fattening on counters. Against a deck that has run dry, or one with nothing it wants to sacrifice, it simply swings for six in the air and ends the game. That conditional symmetry is the whole strategic axis: the demon's value is set by the board state across the table, not by anything you do with it. It punishes empty boards and stalls against full ones, which makes it a clean payoff for aggressive black decks that flood the opposing graveyard faster than the opponent can refill it. The +1/+1 counter is the consolation prize the design grants when the bargain gets taken, turning each tap into a long-term threat that eventually outgrows whatever the opponent can afford to keep feeding it.