Stormkeld Prowler

Cheap blue bodies want to attack early; five-plus-mana spells want you to sit back and durdle toward the late game. This card asks for both at once, which is a stranger pairing than the rate suggests. It fields a 2/1 clock on turn two, then rewards a curve that peaks high, banking two counters per big spell rather than one. The trigger reads mana value at the moment of casting, so cost reduction that shrinks what you actually pay does nothing here; the payoff hinges on the printed number, not the tempo you spend. That distinction is why it can grow to alarming sizes without becoming a tempo trap: one expensive spell turns it into a 4/3, a second makes it a 6/5, and those counters stay put after the spell resolves. It is a bridge card, built to hand a control-leaning or ramp-adjacent blue deck an early threat it would otherwise lack, and to punish an opponent who assumed the slow deck had nothing on board before turn five. The friction is plain: you need the expensive spells in hand and the mana to cast them, and a 2/1 that never triggers is just a 2/1. But the ceiling climbs fast enough that the ask pays for itself when the shell around it is built to reach five mana on schedule.