Deafening Silence is excellent here, shutting off their Brainstorm/Ponder/Flow State/Daze/Force of Will chains that let Dragon's Rage Channeler hit delirium and Murktide Regent grow huge. Erode is an Instant that answers a resolved Dragon's Rage Channeler or Murktide Regent cleanly while letting them fetch a basic, which is fine against their nonbasic-heavy manabase. We cut slower value pieces that don't impact the race, keeping Swords to Plowshares, Solitude, and Thoughtseize as our primary interaction against their low-toughness threats. Aether Vial remains key to deploy Thalia and other hatebears ahead of their countermagic.