Instrument of the Bards

A tutor that keeps its own meter, and the meter is optional. The upkeep trigger only says you may add a harmony counter, which turns the counter total into a dial rather than a clock: park it at one and you have a repeatable tutor that fetches every one-mana dork in your deck, or let it climb rung by rung and reach deeper each turn for progressively larger creatures. The exact-match requirement is the constraint doing the balancing work: you are not searching for your best creature, you are searching for the one whose mana value happens to sit on the current count, so the deckbuilding wants a ladder of legends at ascending costs to keep every activation live. The legendary rider (a Treasure when the fetched card is legendary) closes part of the gap the four-mana activation opens. And because nothing pins the search to your own turn, you can hold that mana up and tutor at instant speed, dodging the sorcery-speed vulnerability that grounds most repeatable search effects. That instant-speed window is the wrinkle: an opponent trying to punish the activation has to guess whether you will crack it in response to their removal or bank the mana. The interplay is where the design lives: the freeze-or-climb decision on one axis, the ladder it rewards on the other, a slow engine when you want it slow and a fixed-value tutor when you would rather stop counting.