Guilty Conscience

Strap this to something that hits hard, and its own swing becomes the kill: every point of damage the enchanted creature deals comes straight back at it, and the Aura is the one doing the dealing. That last detail is the whole design. Because the feedback damage is the Aura's, not the creature's, it carries none of the host's combat keywords; deathtouch on the enchanted creature does nothing to the return shot. The effect is a one-mana answer to a big attacker with thin toughness, but it is pointedly conditional: the trigger fires whenever the creature deals damage, not when it is declared, and it sits dormant on a wall that never deals damage. That dependency on the creature doing something is the restriction that stops a one-mana enchantment from being a clean kill spell. First strike is where it gets sharp: a first-striker deals its damage in a separate earlier step, so the Aura can resolve and finish the creature before a non-first-striking blocker ever swings back. The card's most famous trick is uglier still, pairing with Stuffy Doll to punish an opponent, since the Doll redirects to a player while the Aura keeps feeding damage back. It belongs to white's occasional "your strength is your weakness" corner alongside Pariah, a design space the color visits rarely and never as a staple.