War Dance
Spend one green mana, and you have bought yourself a clock that ticks in your favor. Each upkeep you may seed another counter, and the eventual sacrifice hands a creature +X/+X equal to the count: a pump spell whose magnitude is a function of how long you were willing to wait. Nothing fires the round it resolves; this is a battlefield permanent that costs nothing to sustain and does nothing until you cash it in, at which point the engine is gone for good. That inverts the usual combat-trick math. A conventional pump is a single instant-speed call made in response to a block. Here the commitment is front-loaded, a card and a board slot spent rounds before the swing, with the bonus growing in full view of an opponent who can count the verse counters and brace for the number they imply. The longer it sits, the larger the eventual burst and the more telegraphed the threat, so patience and bluff become part of the calculus rather than reflex. Sitting in a small early-era cycle that all asked the same question (how much delay will you trade for a payoff scaled to the turns you endured), it renders build-around tension as a value you grow in plain sight. The single-use sacrifice is what governs the whole thing: you only pull the trigger once, so every round of additional growth is a round the bonus could already have decided a game.
