Pale Wayfarer

Protection that waits for the board to clarify before it commits is what sets this engine apart from the genre. Most protection effects lock you into a color when you build or cast the card; here, the targeted creature's controller picks the color at resolution, so the situation resolves first and you grant exactly the shielding the moment demands: fogging a swing, voiding a targeted removal spell, or forcing a blocker's damage to be prevented. The leash on all this is the untap symbol in the activation cost, one of the rarest cost components Magic has printed. To pay it, the creature has to already be tapped, so the ability borrows its rhythm from a body sent into combat (or otherwise tapped) and then redeemed for an untap. That gating, welded to a double-white-plus-two mana tax, is what keeps a repeatable single-target answer from ever becoming relentless: you get one activation per tap-and-untap cycle, not a tap-out machine gun. The window itself is generous once the cost is met, firing at any priority, so this functions as genuine instant-speed interaction rather than a sorcery-locked toolbox. What seven mana buys, then, is a sturdy 4/4 stapled to a slow, taxed, color-flexible piece of protection. The tap loop is the real meter on the engine; the per-use cost is almost secondary to the cadence the untap symbol forces.