Tolarian Sentinel

A repeatable bounce engine wearing the body of an evasive blocker. The Spellshaper mold converts a card in hand into an effect for a mana and a tap, and here the effect is the self-bounce: return any permanent you control to your hand. That self-targeting does two jobs that compound. Defensively, it rescues a threatened creature or enchantment by returning it to hand at instant speed, in response to a removal spell that has not yet resolved, so the kill spell fizzles with nothing to hit. Offensively, it re-buys an enter-the-battlefield trigger every turn the loop can pay for, which is where the 1/3 flier earns its keep: it sits behind the engine, blocks the small attackers a control deck fears, and chips in over the top while the discard feeds something graveyard-hungry on the other end. The discard is what stops the ability from being free value, turning it into a genuine resource sink; the tap caps it at one bounce per turn cycle. Both halves of the cost are the leash. A creature that could rescue a permanent and reload a trigger every turn for nothing would warp any grindy mirror, so it costs a card each time and cannot fire twice in a window. This is a hand-shuffling tool built around permanents that profit from re-entering the battlefield, not a clock that closes games in a hurry.