UR Aggro is a mirror-like tempo race built on Slickshot Show-Off and small cantrip-fueled creatures like Elusive Otter and Pompous Battlemage, making Fire Magic's Fira mode (2 damage to each creature for {2}) a clean sweeper against their whole early board. Impractical Joke is redundant with our own Burst Lightning and less efficient than Fire Magic here, and Get Out/Spell Snare are cut down since we want proactive damage and pressure more than reactive counterplay against their low-cost spells. Colorstorm Stallion races their clock while dodging their Burst Lightning (needs kicker for 4) and Sunspine Lynx doesn't block well into our bigger threats. Spell Pierce protects our key spells from their own Spell Pierce/Spell Snare while we race.