Daemogoth Woe-Eater

Seven power for four mana buys a body that dwarfs almost anything in its color pair, and the printed cost is only half the reason it stays honest. The upkeep sacrifice is the real tax: every turn you keep this on the battlefield, you feed it a creature, so the demon runs on a supply chain rather than sitting idle. That is the older demon-tax lineage (creatures like Lord of the Pit that eat a body each turn or maim you) reworked into an engine you can actually want to build around. The wrinkle is the second ability, which fires when you sacrifice the Woe-Eater itself: opponents discard, you draw one card, you gain two life. So the upkeep tax that looks like a liability becomes the exit ramp. Sacrifice fodder feeds the beast until the beast is the fodder, cashed to a sacrifice outlet for a life-positive draw with a discard rider attached, ending your own obligation on your terms rather than watching a board of chaff evaporate to it. It is a creature built to be a temporary asset: a giant blocker and attacker while it lives, a card-advantage payoff when it's sacrificed, and a self-solving problem in between. The design asks you to have a plan for the day you no longer want to pay upkeep, and rewards you for having one.