Frostwind Invoker

The eight in that activation cost is doing all the design work, and it is set there on purpose. Tuned high enough that the ability is pure fantasy through the early turns, then trivially payable the moment a game stalls out and lands keep coming, it converts a fine-bodied 3/3 flier into a board-wide evasion grant precisely when ground combat has locked up. That is the entire logic of the Invoker template: a recurring common-rarity design that bolts one steep, deckbuilding-free mana sink onto a creature, so the card costs you nothing to run and pays off only when the resource it asks for has stopped being scarce. The body keeps you honest while you wait, trading and blocking like any other five-drop, and the activation turns surplus mana into reach over the top of a clog. There is a small wrinkle worth naming: the grant covers your whole team, not just this one, so the payoff scales with how many bodies survived the standoff rather than with the Invoker itself. It rewards the long game without demanding anything of you up front, which is exactly the design brief: a topdeck that gets better with every land you draw after the curve has run dry, and a closer that ends a stalled board in a single evasive swing.