Chisei, Heart of Oceans

A flying 4/4 for four mana is a fair rate on its own; the upkeep tax is what makes Chisei a puzzle rather than a beater. The Spirit demands a counter every turn or it leaves play, which sounds like a downside until you read it as a permission engine. Any counter on any permanent you control feeds it: a +1/+1 counter, a fading or vanishing counter, an age counter from a cumulative upkeep card, a charge counter on an artifact. The design hands you a slow, mandatory drain that you can aim wherever it does the least harm, or the most good. The era this comes from was thick with counter-based mechanics on permanents you would happily strip a token from, which is the trick: pair Chisei with something whose counters you wanted gone anyway and the upkeep cost inverts into upkeep value. The tension the card resolves is between a strong evasive body and the recurring price of keeping it, and it resolves that tension by outsourcing the cost to your own board. Left in a deck with no counters to spare, it sacrifices itself on turn two of its life and the line is dead. Surrounded by the right permanents, the tax becomes a clock you control: a deliberate piece of build-around design that rewards a board state engineered around shedding counters one at a time.