Andradite Leech

A pump activation that taxes its own deck is a strange thing to print, and the tension is the entire reason this exists. The repeatable +1/+1 wants black mana, and so does every other black spell you cast, because each one now costs an extra black to put on the stack. That self-tax is the price the design pays for an otherwise unbounded growth ability on a 2/2 body: in a pure mono-black shell where black mana is plentiful, the tax bites every removal spell and every threat you try to deploy, so the creature you would most want to grow is the creature that makes the rest of your hand worse to play. The Leech is built for a board state, not a curve: late in a long game, when you have flooded out and have nothing better to spend black mana on, it converts that excess into a clock. The activated cost and the symmetry-breaking tax are the same color of mana on purpose, forcing a turn-by-turn decision about whether to grow the body or cast the spell. The drawback lives in the body itself rather than buried in a finality counter or an upkeep trigger, and it is unusually pointed: it punishes the very deck most inclined to run it.