Izzet Spellementals is a UR Aggro shell of entirely red and blue spells, so Flashfreeze is live against Burst Lightning, Prismari Charm, or a Slickshot Show-Off. An additional Deadly Cover-Up helps reset the board against their Eddymurk Crab and Otter tokens before they overrun you. Strategic Betrayal is weak since they rarely commit to a single standout threat worth exiling, and Duress is low-impact against a low-curve tempo deck without one clear key card. Use Nowhere to Run and Sear to pick off Slickshot Show-Off before it connects.

UR Aggro is entirely red and blue spells, so both copies of Flashfreeze are live to stop Burst Lightning, Colorstorm Stallion, or a key Slickshot Show-Off. A second Deadly Cover-Up gives you more sweeper density against their go-wide creature tokens and Eddymurk Crab. Strategic Betrayal is weak here since they have few standout single creatures worth exiling and it does nothing about their spells, and Duress is less impactful against a low curve, tempo-oriented deck that doesn't rely on one key card. Prioritize surviving to your sweepers and Jeskai Revelation to reset the board and stabilize.

Azorius Tempo has no red or green spells, so Flashfreeze is dead against them and should stay in the board. Duress strips their key enablers like Airbender Ascension or High Noon before they can set up Aven Interrupter or Enduring Curiosity, while Strategic Betrayal answers a resolved Aang, Swift Savior and clears their graveyard. Together as One is too clunky at six mana against a deck full of cheap interaction like Aven Interrupter. Lean on Deadly Cover-Up and Nowhere to Run to handle their evasive flyers.