Kill Switch

The premise is a soft Stasis aimed at one card type, and it carries Stasis's central paradox: the lock holds only as long as the source stays tapped. Activate Kill Switch and every other artifact freezes; the moment it untaps, the whole board breathes again. The cruel wrinkle the design hangs on is that Kill Switch has no clause letting its controller keep it down. It untaps automatically during the untap step like anything else, snapping the lock open every turn cycle and demanding another to re-engage. That makes the prison a metered subscription rather than a one-time toll: you pay each turn to keep the cell door shut, and declining the untap is not an option. The recurring is what balances the card. The lock is never free to maintain, so the design asks its controller to commit a perpetual tax for the privilege of stopping everyone else's mana rocks, equipment, and artifact combo pieces. The symmetry is brutal in a deck leaning on its own artifacts, since the freeze hits all other artifacts indiscriminately. What keeps this a designer's curiosity rather than a staple is how narrowly it bites: against one or two artifacts, the recurring cost outpaces the disruption; against a board built on artifacts, a single tap shuts the whole engine down while you sit behind noncreature threats. It is a lock that wants its controller to want to do nothing else, then charges rent for the pleasure.