Chupacabra Echo

Removal that scales with your graveyard has a payment problem built in: permanents don't fuel it by being cast, they fuel it by dying, milling, or getting sacrificed. This one counts permanent cards specifically, not the whole bin, which tethers it to a deck that grinds lands, artifacts, and creatures into the yard rather than one just churning instants and sorceries. Early it's a 3/2 that trims a blocker by a point or two; later it comes down with a hard removal spell stapled to its front, and the arithmetic keeps climbing as long as the pile grows. The friction is that the body and the -X/-X want opposite decks. A 3/2 for four mana wants to attack, but the shrink only starts erasing things in a slower, permanent-heavy shell where the counting takes several turns to matter. Because the effect keys off entering the battlefield, any blink or reanimation re-aims it at a fresh target, and by the second or third arrival X is usually large enough to kill almost anything. That's the honest ceiling: not the stat line, which is forgettable, but the repeated entries, when the graveyard has finished its accounting and the number has quietly grown big enough to erase the format's top-end threats.