Dehydration

Pseudo-removal that never kills anything: it switches off the untap step, so once the enchanted creature taps, it stays down. The Aura form is the catch. Permanent removal answers a creature for good; this answers it only while it sits tapped, which puts a premium on when you cast it rather than on the four mana itself. The Aura doesn't tap the creature on its own, so casting it on something already untapped buys nothing immediately: the body can still attack once (which taps it, locking it the moment it does) or block at will, and only stays disabled once its controller commits it to something. Land it where the body is already tapped from attacking or activating an ability, and the lock snaps shut on resolution. That gap between "enchanted" and "disabled" is the fragility of the design. Four mana buys a persistent disabling effect that generates no card advantage and neutralizes one body, and it can be unwound on the opponent's terms: bounce returns the creature to hand and sends the Aura to the graveyard, and any enchantment removal frees the body outright. Charging a premium is what holds a never-expiring tap-down effect in check, but it pays for a soft lock the opponent gets several angles to break. That undoability is exactly why later tap-down designs migrated toward stun counters and one-shot effects rather than persistent Auras an opponent can answer at leisure.