Panglacial Shinobi

Ninjutsu ordinarily reads off your hand: swing with an unblocked attacker, return it, drop a ninja in its place. This one runs the same swap off your library, the zone you have almost no scheduled access to during combat, which is why the ability is welded to a phrase that appears on only a handful of cards: "Activate only while searching your library." You have to already be digging through your deck (a fetch effect resolving, a tutor mid-resolution, some search effect actively resolving) at the precise moment an attacker of yours goes unblocked, and only then can you pay the , shuffle that attacker away, and put this in tapped and attacking for a card off the top. The Wurm Ninja type line runs the same absurdity from the flavor side: a creature-type mashup that exists to be nonsensical, bolted to a function most games will never let you reach. What lifts it above pure novelty is that it is a genuine study in gating by zone rather than by cost. The mana is trivial; the real barrier is that the rules keep you out of your library nearly all the time, so the ability can only fire inside a window you have to manufacture. It rewards the player who deliberately assembles the search-and-swap sequence, not the one who stumbles into an open library by accident.