Cloudsteel Kirin

The "you can't lose the game and your opponents can't win the game" clause has a long, awkward history: Platinum Angel bolts it to a fragile flier that hands the lock right back the moment it dies, and Angel's Grace rents it for a single turn. Stapling that text to a body always runs into the same trap: the body is the failure point, and a creature that just sits there daring an opponent to kill it means you have paid full price for a target. This design sidesteps that by making the carrier useful before it ever becomes insurance. A 3/2 flier for pressures the board immediately, and only later, once you have a creature worth shielding, does Reconfigure convert it into a can't-lose lock strapped to something sturdier. That two-stage life keeps the card from ever going dead: it starts as a flier you were happy to cast anyway. The Reconfigure cost is what keeps the whole thing honest. Moving the shield is a full turn's sorcery-speed commitment, so an opponent gets a window to remove the intended host before the armor snaps on, and the lock is only ever as durable as the creature wearing it. Kill that creature and the "can't lose" text leaves with it. What it buys is the conversion of any slow grind (a mill clock, an incremental drain, a stalemate) into a race the opponent literally cannot win, so long as the warded creature stays on the battlefield.