Ring of the Lucii

Two colorless off a rock is the floor; the real reason to reach for it is the ability tucked underneath. For two mana, a tap, and a point of life, it locks down any nonland permanent: a blocker cleared before combat, an attacker stood down before it swings, a mana rock or utility artifact kept off its activation for a turn. Reaching past creatures to any nonland permanent is what separates it from the older tapper line; the classic version of this effect, Icy Manipulator, hits artifacts, creatures, and lands but never touches an enchantment or a planeswalker, and the split here trades away lands for everything nonland. Because the effect is repeatable and instant-speed, it plays less like a one-shot tap and more like a standing tax on whichever permanent matters most each turn, paid one life at a time. Time it on an opponent's upkeep, before they have spent their turn, and you can tap down a mana rock or dork so they either float that mana immediately or lose it. The tension is built into the shared tap: on any given turn the ring is either fixing your mana or interfering with theirs, never both, and that opportunity cost is what keeps a repeatable soft-lock from curdling into oppression. It is a mana source doubling as a control valve, with the life payment as the throttle that keeps the valve from ever being free.