Azorius Tempo fields a lot of small flying threats (Sage of the Skies, Momo, Friendly Flier, Starfield Shepherd) that go wide and stabilize, so we need interaction that scales. Sear is an instant, so we can kill a creature in response to Daydream or Practiced Offense and blow out the trick, and its 4 damage also reaches slightly bigger bodies like a Guiding Hydra with a few counters. Impractical Joke's 3 damage does kill Starfield Shepherd and Sage of the Skies (including a copied token), but it is a sorcery and weaker against a grown Hydra, so we trade it for the more flexible Sear. Quantum Riddler is a 4/6 and survives both, so don't count on burn for it. Spell Pierce is strong against their noncreature spells like Daydream and Practiced Offense when they're tapped low on mana early. Vibrant Outburst's ceiling is lower than dedicated removal here. Race aggressively since this matchup is close and tempo-positive draws win.