The Millennium Calendar

The number 1,000 is the joke and the design constraint in one: a life-loss payoff so absurd that reaching it has to feel like solving a puzzle rather than passively accruing value. The engine is exponential, not linear. The untap trigger deposits counters in a lump equal to however many permanents you untapped, so the payload scales with how greedy your untap step is; the more lands and creatures you leave tapped one turn to untap the next, the fatter the base you start from. Then the activated ability doubles the whole stockpile for two mana, and doubling is where the arithmetic turns lethal. From a single seeded counter it takes ten doublings to clear the thousand-mark, but every one you can accumulate off the untap trigger first cuts that chain shorter. That interplay is the actual game: the untap trigger is the accumulator, the activation is the amplifier, and the card rewards a wide board precisely so the doublings have fuel to work on. The sacrifice clause is not optional and does not wait for your say-so; it fires the instant the count crosses the threshold, so the whole enterprise is a countdown you are racing to accelerate rather than a resource you get to bank and admire. It belongs to the tradition of comedy-payoff artifacts whose entire appeal is the improbability of the number printed on them, built to be chased for the story of getting there as much as for the kill.