Glissa Sunseeker

The destroy ability hides a riddle most players failed to solve at the table: the destruction only happens if your unspent mana exactly equals the target's mana value, which means you tap her, hold up a precise pool, and pray your opponent does not change the equation in response. There is no "destroy any artifact" here. Surrounded by artifacts of every cost, she could in theory dismantle any of them, but the arithmetic turned each kill into a small puzzle of mana management rather than a free swing: leave four floating to crack a four-drop, two for a two-drop, zero for a Mox. The first strike on a 3/2 body is the part of the card that works without the calculator. The trouble is that the ability is precisely as awkward as it is flexible. Naturalize destroys any artifact for two mana and asks nothing of your mana count; Glissa demands you spend a turn arranging your lands like coins to make exact change, then commit a creature's tap to the bargain. She is an early, unrepeated experiment in pricing removal by a condition you control but must satisfy perfectly: not a cost in mana so much as a constraint on how that mana is held. It is a design knob Wizards tightened once and has mostly left untouched since.