Orzhov Control's removal suite (Fatal Push, Vanishing Verse, Get Lost) and planeswalkers make Fires of Victory less reliable, so those slots are better spent on cheap countermagic. Change the Equation's first mode counters their cheap interaction and disruption, such as Thoughtseize, Fatal Push, Vanishing Verse and Get Lost, and also cheap permanents like The Queen of Dale, The Ooze and Obsessive Pursuit. Note that it only reaches mana value 2 or less, so it cannot counter Caretaker's Talent, Skyclave Apparition or Sanctum Lurker (all mana value 3). Its red-or-green mode has no targets in this matchup, since Orzhov plays neither colour. Keep Volcanic Spite, Fiery Impulse and Fable of the Mirror-Breaker as proactive pressure, since this is a grindy matchup where card advantage and resilient threats matter most. Watch for Thoughtseize and Duress stripping key interaction before you can deploy it.