Dimir Terror is another all-blue-and-black shell, so Red Elemental Blast is maximally live — counter their Counterspell or a cheap Tolarian Terror, or destroy a resolved Tolarian Terror or Gurmag Angler outright. Obsidian Acolyte's protection from black shuts down their Snuff Out and Agony Warp as removal against it, letting it hold the ground or keep attacking. Their threats get cheaper the longer the game goes thanks to Thought Scour and Mental Note filling the graveyard, so prioritize proactive pressure and disruption over the reactive Loran's Escape and Sandstorm Eidolon, and cut the tempo-negative Boros Garrison to keep your curve tight against their counterspell-backed tempo plan.