Mistral Singer

An evasive prowess body is the cleanest expression of what a spells-matter aggro deck wants: something to carry the extra damage a hand full of cheap noncreature spells generates, over the top of a stalled ground. A 2/2 flier on its own is unremarkable, but each cantrip or burn spell cast in the same turn pushes the clock to 3 in the air, then 4, and flying means those bumps land where ground blockers cannot follow. Prowess rewards the turn you spend spells rather than the turns you hoard them: the buff evaporates at cleanup, so a spell-dense line has to convert into damage in the same window it fires, not bank value for a later grind. That is the tension it resolves for blue, a color whose native card-advantage instinct is to sit behind its spells and durdle; here the spells become fuel for a body that closes the game while they are being spent. Sirens fill a role blue does not otherwise price cheaply, an aggressive flying beater built to attack rather than defend, and this one earns its keep by translating a loose pile of cantrips into a fast aerial finish rather than a hand of unused card advantage.