Storm Fleet Aerialist
Raid is a reward that arrives backwards: the bonus you want depends on combat you already committed to before this creature was on the board. That makes it a tempo payoff dressed as a curve play. Play it on a quiet turn where nothing has swung, and it is a fragile 1/2 flier with little to recommend it; play it the turn after your one-drop or two-drop has already attacked, and it lands as a 2/3 evasive body that keeps the clock ticking. The counter, not the flying, is where the design lives, because it asks you to sequence aggression rather than just deploy threats: attack first, develop second, and the same two mana buys a meaningfully bigger creature. That conditional doubles as a self-limiting mechanism, the check that stops an aggressive blue flier from being unconditionally efficient. The reward is small in absolute terms, one +1/+1 counter, but the structural lesson is the interesting part: it teaches a blue deck to think like a red one, to spend its early turns attacking instead of reacting, and to treat the combat step as a resource the rest of the curve can cash in. Putting an aggressive payoff in a color that historically would rather hold up countermagic is the whole gamble, and Raid is how the card makes that gamble pay only when you have actually chosen to be the beatdown.
