Skullmane Baku

The Baku cycle took Kamigawa's spellcraft-counting hook and gave each member a different release valve for the stored charge; this one points the stockpile at an enemy creature and shrinks it. Casting Spirits and Arcane spells feeds ki counters that later convert into repeatable, scalable removal: spend one for a small -1/-1 nudge, or dump the whole reserve into a -X/-X big enough to bury a real threat. The conversion rate is the balancing act. You only bank counters by committing to a board of Spirits and Arcane spells, so the removal runs only as deep as your spell density, and every counter you spend is a counter not saved for a single decisive shrink. The fragile 2/1 body and the activation that wants mana on top of the tap keep the engine from being a free splash: this is a tribal payoff, not a generic answer, built to reward the deck the rest of its cycle assumes you are playing. Unlike a one-shot kill spell, the counters persist, so a Skullmane Baku that survives a few turns becomes a standing tax on whatever the opponent commits to the board, a charge that never decays until you decide to discharge it.