Nebelgast Intruder

The tempo play disguised as a combat trick. Flash on a flying body already lets a Spirit ambush an attacker or hold up a bluff, but the enters trigger is where the real work happens: shrinking an opponent's creature's power by two for the turn turns an even block into a lopsided one, or lets a smaller attacker crash through unanswered. The trigger is optional and can target nothing, so it never rots in hand against a bare board. What makes the design tick is the asymmetry between what it costs and what it accomplishes on defense: flash it in once the opponent has committed to attacks, eat a creature in combat, and keep a 2/1 flier that pressures back the next turn. The -2/-0 is deliberately blunt: it does not kill, it does not stick, it only buys the current combat step. That temporary window is the whole reason a card this cheap can afford to be a flier with flash. This is blue's tempo-Spirit tradition in miniature, an evasive body built to trade up in the air while nudging combat math in the caster's favor, paying partial rent as removal without ever being removal.