Outrider en-Kor

The free damage-redirection ability is why this Rebel persisted long past any combat it was designed for. The en-Kor mechanic shunts incoming damage onto your own board for no mana, which reads like a defensive trick: shrug off a blocker, absorb a burn spell. But the activation costs nothing, and that is the trap. The cost means the ability can be put on the stack an arbitrary number of times in a single turn, and each activation is itself a targeting event. The infinite loop never moves any damage at all: pair the card with something that triggers off being targeted by this ability (the classic partner is a creature that mills or grows each time it becomes the target), and you have a free button you can press until your library is empty or your win condition is online. No damage needs to be dealt; the loop is built entirely out of the repeated activation, not out of bouncing a single point back and forth. This is the artifact-of-design version of "the ability is the body": the 2/2 with flanking is filler, and the activation line is the card. That is what makes this kind of design treacherous to evaluate, a clean balanced front bolted to a zero-cost button that is benign in isolation and degenerate the moment the right partner exists. The flanking is flavor; the redirection is the reason anyone ever wrote its name on a decklist.