Shacklegeist

A tapper that runs on bodies instead of mana, and that distinction is the whole design. The classic tappers, from Master Decoy to Blinding Mage, pay in tap-plus-mana or ride on a sizable investment; this one asks for a quorum instead. Two untapped Spirits, tapped as a cost, keep target opposing creature down: no mana, no summoning limit, just a standing tax that a wide Spirit board can levy every turn. The ability scales with the deck it wants you to build. One activation locks down a blocker or a nascent attacker; several activations across a developed board can freeze an opponent's whole offense, since the cost draws on a resource (untapped Spirits) that a tribal deck naturally floods. The blocking restriction is the counterweight: a 2/2 flyer that can only intercept other flyers is a narrow wall on defense, which pushes the card toward the aggressive, board-building side of the archetype rather than the reactive one. It turns the Spirit type line itself into repeatable, removal-adjacent control, and because the ability fires at instant speed, the timing window is precise: tap the biggest threat during your opponent's beginning-of-combat step, before they declare attackers, and it sits out the turn entirely. Wait until after attackers are declared and you have missed the window; a tapped attacker is still attacking. Used on the right side of that step, the ability is a soft pin that never lets the creature swing at all.