Thryx, the Sudden Storm

The tension in every big-spell control deck is timing: you want to hold up a haymaker at instant speed, but the payoff finisher wants the turn to itself. This Giant collapses that gap. It arrives at flash speed to plug an open board or answer a threat, then rewrites the economics of everything expensive still in hand, shaving a mana off each five-drop-or-larger and, more consequentially, wrapping them in an uncounterable clause. That second rider is the real design work: the discount is convenience, but the counter-immunity turns a fair top-end into a resolution guarantee, upending the usual control mirror where the deck with the last counterspell wins. The 4/5 flying body is priced to matter on the ground as well as the air, so this is not a fragile enabler that folds to a stray burn spell. What holds it in check is the same thing that makes it powerful: it only aids the top of your curve, so it rewards a deck genuinely built around bombs rather than one that happens to run a couple. The flash matters most for sequencing across turns: land it on an opponent's end step, untap, and the discounted, uncounterable finisher resolves with the body already deployed and the mana already freed. It is a cost-reducer and a shield stapled to a defensive frame, aimed squarely at the archetype that has always most wanted both.