Nim Abomination

A 3/4 for three is an aggressive body in black, and the drawback explains exactly why you get it: every one of your end steps you leave this thing untapped, you bleed three life. That clause turns a stat line into a clock pointed at its own controller, and it rewards the one thing creatures want to be doing anyway. Attack with it and it ends the turn tapped, sidestepping the loss entirely; sit back to block and the payment comes due. The design pins the card's power to its willingness to commit, a tension that reads as pure aggression: defense is taxed, offense is free. Vigilance becomes its quiet nemesis, since a creature that attacks and stays untapped collects the punishment regardless. It also slots into the small family of cards that treat your own life total as a spendable resource, where three points a turn is a cost you accept while the body keeps the pressure on and discard the instant the math turns against you, whether by chump-blocking it away or tapping it to some other use. The Nim flavor (irradiated salvage drones scavenging across the wastes of Mirrodin) suits a creature that is steadily killing the thing wearing it.