Myr Scrapling

A one-mana body that exists to be spent, converting itself into a permanent stat bump on something that matters more. The wrinkle is the direction of the sacrifice: most cheap fodder feeds an outlet you already control, while this one staples the conversion to the creature itself, turning a spare 1/1 into a +1/+1 counter at will without an Ashnod's Altar or a Viscera Seer standing in the way. That self-contained shape earns it a second job as a combo piece. Persist creatures return with a -1/-1 counter; sacrificing this to drop a +1/+1 on them cancels the two, resetting the persist trigger so the loop can fire again. On its own the effect is one-shot: the sacrifice is the cost, so a single Scrapling counters exactly one -1/-1 and then it is gone. The repeatability lives in the wider engine, where a stream of bodies (or a way to recur them) keeps the counters flowing while some other outlet, a sacrifice payoff or an aristocrat trigger, does the actual killing. It also serves fair beatdown that wants a body to swing with early and a counter to place later, since the ability rides on the creature rather than a separate outlet you have to assemble. Aggression up front, combustible material once the game becomes a puzzle: quiet double duty from a card that reads like filler.