Tree of Redemption

That 13 in the toughness box is not a wall: it is a number waiting to be poured into your life total. The activated ability swaps your life total with the creature's toughness, and because an untouched body sits at toughness 13, the first activation sets your life to 13 the instant you point it at yourself. The engine lives in the inversion. Buff the toughness past 13 with anything that pumps it (an Aura, a +1/+1 counter, a static anthem) and the exchange becomes a life-gain spike scaled to how high you can push the body. The swap is symmetric, which is what lifts it above a one-way heal: the exchange sets the creature's base toughness to your previous life total, and any static pumps still on it continue to apply on top of that new base. The accounting runs both directions, so each activation rewrites both halves and you can keep feeding the toughness between swaps, treating it as a repeatable dial rather than a single burst. Defender keeps it from being the finisher: a 0-power blocker can stall, refill your life, and serve as an enormous body for the toughness-matters cards that want something this big to point at, but it cannot close the game alone. This is toughness-as-resource design at its most literal, a creature whose stat line is the spell.