Black Oak of Odunos

A 0/5 with Defender is a wall by trade, and the activated ability is the design's whole twist: it lets the wall grow, but only by spending the rest of your board to do it. Each black mana and each tapped creature buys a single point of size, and the size lands on the one creature that cannot use it to attack. So the loop never converts to offense; it converts to immovability. A wide board where individual bodies are expendable feeds the engine best, every dork or token tapped into the Oak making it a blocker nothing small can profitably swing into. The catch is that you are paying for that resilience with everyone else's tempo: the creatures you tap are the creatures you might otherwise be attacking or blocking with, so the wall thickens precisely when your offense thins. As color-pie reasoning, this is black solving a defensive problem with a sacrifice-adjacent cost, buying durability by cannibalizing its own resources rather than the opponent's. The Zombie Treefolk typing is the flavor seam where a heroic-myth setting met its underworld: a tree drained of life and pressed into service as a tireless sentinel. Built for grind, not tempo, the ability does little if you slam it into a wide deck with nothing to protect; held up across a turn while the rest of the board closes the game, it soaks attacks indefinitely.