Hydroblast is dead against this all-blue Temur mirror-adjacent deck and should stay boarded out. Aura Flux punishes their Stasis by forcing an upkeep payment or sacrifice, which can break their lock plan if they're tapped out or low on mana. Essence Flare is a slow answer with limited impact here since they run few creatures, so it's a marginal include mainly against Black Vise pressure being irrelevant — consider it a low-priority swap. Focus the matchup on out-countering and out-drawing them with your denser Counterspell/Foil/Daze suite, since this is fundamentally a battle of card advantage and tempo.