Jötun Owl Keeper

Most permanents with cumulative upkeep treat the climbing tax as a curse: each turn adds an age counter, each age counter raises the toll, and the keyword's whole reputation is the day the cost finally outpaces the body and you let it die. This Giant inverts that arithmetic. The same age counters that make it harder to keep alive are the counters that fix the size of its death payoff, so every upkeep you pay is not just rent on a 3/3 but a deposit on a flock of fliers. When it dies, it hatches a 1/1 white flying Bird for each age counter it carried, which means the natural endgame (paying the tax until you can't, then sacrificing or trading the body) is also the engine's full execution. The flexible or payment is a quiet nod to two-color decks, but the real design idea is the reconciliation of cumulative upkeep with value: rather than asking you to wring use out of a permanent before it collapses under its own cost, the card converts that accumulated cost directly into a board. The mechanic everyone else learned to dread becomes, here, a reason to want the counters to pile up: a self-funding bird factory disguised as a tax you're forced to pay.