Hungry Spriggan

The printed body is a deliberate lie: this creature shows up as a meek 1/1 and swings as a 4/4, with trample to carry the difference past a desperate chump. The pump fires every combat and wears off each turn, so the math runs backward from what the card looks like at rest: it is at its smallest exactly when it would block or hold the line, and at its largest the instant it points itself at a player. That asymmetry is the entire trade. On offense it represents four trampling power for three mana; on defense it dies to any one-drop that bothers to attack into it. The +3/+3 stacks cleanly with anything else aimed at the attack: an instant-speed pump layered on top of the trigger, a second combat that re-fires the buff, an anthem the opponent's blocking math never budgeted for. And because the swing resolves when attackers are declared, before blocks are committed, a lone small blocker rarely eats more than a point or two of the enlarged body. It is a clean expression of a recurring green idea that long predates this printing: pile the reward onto attacking, let the defensive case rot, and let the card move exactly as fast as the deck around it wants to go.