Royal Trooper

The defensive math is the entire pitch: a vanilla body on offense, a 4/4 the instant it's declared as a blocker. That conditional swing reframes how an attacker reads the board, because the 2/2 they're sizing up isn't the creature they actually have to trade with. Anything sending a 3-power threat in expecting a favorable exchange runs into a wall that grew two sizes after blockers were declared, and the +2/+2 lands too late to be played around once attacks are committed. It's a classic asymmetric design from the era of clean common-rarity soldiers: priced and bodied like an unremarkable midrange creature so it never demands a card to deal with proactively, but punishing on the turns its controller chooses to stand still. The cost of that wall is that it does nothing for you on the attack and nothing at instant speed in your own combat math; the bonus only fires on the block, so the card is a deterrent rather than a threat, valuable precisely to the player who'd rather not be the aggressor. It's the kind of body that quietly makes opponents redraw their attack steps without ever needing to swing itself.