Scepter of Dominance

Repeatable tapping looks tame and almost never is. The timing carries the whole effect: activate it on an opponent's upkeep, after their untap step has already passed, and the permanent stays tapped through their entire turn. A creature held tapped misses combat and cannot block; a land held tapped produces no mana; an artifact or creature with a tap ability cannot be fired. This is denial through repetition, not a single decisive swing. White's color identity rarely gets persistent, no-strings interaction like this; the Scepter sits with the patient, attrition-minded half of the color rather than the go-wide half. There is a genuine seam in the design, though: the Scepter taps to use, so it handles one target per turn, and that bottleneck is the only reason it does not amount to a hard lock by itself. Aim it at a single permanent every upkeep and that permanent stays pinned indefinitely; the one-target ceiling is exactly what an untapper buys past, freeing the Scepter to pin a second permanent each turn rather than just the one. The most punishing line is tapping an opponent's only mana source on their upkeep, a soft mana-screw applied one increment at a time, the grinding repeatable interaction that rewards a deck content to wait an opponent out of resources.