Unwinding Clock

Vigilance, but for the mana rocks. The whole effect lives in one structural inversion: instead of granting a second untap step on your own turn, it untaps your artifacts during everyone else's. The math compounds with the table. At a four-player game that is three extra untaps per round, which means a tapped artifact stops behaving like a once-per-turn resource and starts behaving like one you can wring value from on any player's turn. Artifact tap abilities are already usable at instant speed; what this card changes is availability, not timing. A mana rock, a Mind Stone-style draw engine, an activated removal artifact: each becomes something you can fire on every untap step in the rotation rather than once on your own. That rewards high-cost activated abilities and engines that want to tick on opponents' turns, where holding up an effect would otherwise cost you a full turn cycle. The cost is that the card produces nothing on its own line; it needs artifacts worth untapping, and its power scales directly with how many untap steps belong to other people. That is also why it stays a multiplayer card: the more opponents, the louder it gets, and against a single opponent the effect is barely more than a slight tempo gain. The design idea worth the slot is precisely that inversion: a permanent that cares about other players' phases instead of your own.