Zephyr Sentinel

Flash and flying make for a fairly priced evasion package on a two-mana blue body, but the arrival clause is what turns the Sentinel from a combat trick into a value ferry. Bouncing your own creature at instant speed rescues something from a removal spell in response, recycles a departure-and-return payoff for a second use, or lifts a blocker out of harm's way, and the Sentinel does the ferrying on its own way in. The conditional counter is the tell: it wants a Soldier specifically as the target, folding the card into a tribal loop where each recursion leaves the flier a little bigger. That reward is narrow enough not to be free (a random creature just resets a trigger; a Soldier also grows the board), but it aligns the card's two jobs, protection and pressure, along a single axis rather than splitting them. Flash carries more weight than the 2/1 suggests: hold it up and you flash it in as a surprise blocker, or on your own turn return a threatened attacker of yours to hand before damage, or ambush an incoming flier and still bank the bounce. The catch is that a returned creature comes back summoning-sick unless it has haste, so the trigger buys value and dodges removal rather than an extra attack. A modest rate carrying a lot of decision-making, the kind of interactive two-drop built for a deck that wants to trigger the same handful of value creatures again and again.