Greasewrench Goblin

Red rummaging (discard cards, then draw that many) usually rides on pricier bodies or burns off as a one-shot spell, because it is the color's cleanest patch for its thin card advantage and would be unfair as a repeatable engine on a cheap frame. Stapling that filtering to a 2/1 for a single red only works because the ability fires exactly once and then never again: the exhaust clause is the price that keeps the rate honest. The single activation is what makes the math balance, and everything else in the design is built on top of it. Discarding up to two here reads as fuel rather than cost. Pitching a card you would rather cast from the yard, or looting toward a reanimation target, converts the downside of rummaging into its purpose, and the +1/+1 counter means the three mana you spend to dig also nudges the body to a 3/2 instead of leaving a stalled attacker. The tension is clean: you buy flexibility and a small stat bump once, and afterward the Goblin has to earn its keep on combat alone. It is a compact statement of the exhaust philosophy, that a genuinely strong effect turns fair the moment you can reach for it a single time.