Rhet-Crop Spearmaster

A 3/1 is the bluntest aggressive body white prints: all reach, no resilience, dead to anything that pings a single point. Exert reframes that fragility as a choice made in the attack step rather than at deckbuilding. Swing without exerting and you have a vanilla 3/1 that trades down against almost anything; exert and it swings as a 4/1 first striker that kills most blockers before they ever hit back. The catch is the ones it does not kill: with a single point of toughness, a blocker that survives first strike (or one that was never going to die to four damage) still trades with it in regular combat, so exert rewards you for reading which blocks are lethal and which only look scary. And the price comes due later regardless: an exerted attacker skips your following untap step, so each aggressive swing borrows against next turn's board presence. That is the tradeoff the mechanic was built to explore, and this body isolates it about as cleanly as it can be isolated. First strike solves the toughness problem in combat and nothing else; burn and point removal still kill it, so the card never pretends to grind. It races. Where most pump effects want you holding up mana at instant speed, here the resource being spent is tempo already committed to the board, and the math only rewards the exert when you hold the initiative and your opponent is the one deciding whether to block.