Containment Membrane

Pacifism with a different switch: instead of forbidding a creature from attacking or blocking, this Aura simply denies its untap step, freezing whatever it lands on until the enchantment leaves the board. The wrinkle is that the lock only bites once the creature has already tapped, so it reads less as a preemptive answer and more as a way to keep a committed attacker or tapped blocker from ever coming back around. That timing constraint is the whole character of the card. It rewards the player who lets the opponent overextend and then answers the creature at the point of maximum inconvenience, rather than trading proactively. The surge cost sharpens that further: shaving two mana off the price when you have already spent this turn nudges a reactive Aura onto an aggressive curve, letting a tempo deck deploy a threat and chain the lock behind it in the same turn. The design asks you to play forward instead of holding the answer in reserve. The friction sits in what can undo the lock: anything with vigilance never taps into the trap, and any untap effect or a flash-in blocker either escapes it or arrives too late to be caught. So the card lives or dies on the opponent committing the exact creature you most want stranded, which makes it precise and punishing when the read is right and inert when it is wrong.