Seraph of the Sword

A flier that never loses a fight in the air. The damage-prevention clause turns combat into a one-sided proposition: blockers bounce off it, would-be attackers find the trade refused, and the only way through combat is to stop trading blows entirely. That asymmetry is the whole pitch. Against an aerial assault it walls off the skies and stalls; against a ground assault it can drop back and block, eating attackers turn after turn without taking a scratch. On offense it forces the opponent to chump it forever or trade resources at a profit they cannot match. The body is deliberately modest so the prevention does not become oppressive: the clause only shrugs off combat damage, so a 3/3 that survives every block still folds to a removal spell, a sweeper, a fight effect, or a deathtouch source that connects some other way, and it can be chump-blocked indefinitely without ever clocking out a control deck. Note the limit precisely: it prevents combat damage, not death, so anything that kills without combat still kills it. The flavor is the cleanest part of the design: an angel whose shield turns aside every sword, written into the rules as permanent immunity to the one thing creatures normally fear from each other. It is a defensive specialist wearing a flier's wings, one that quietly wins races it has no business winning because the opponent's clock simply stops working against it.