Dimir Excruciator is a midrange-control deck built around Doomsday Excruciator and Superior Spider-Man as threats backed by discard (Duress, Bitter Triumph) and card advantage engines like Emeritus of Ideation and Stock Up. Rest in Peace is a high-priority sideboard card to disrupt any graveyard synergies while also blanking Winternight Stories. Bring in Flashfreeze and Annul to protect your key permanents and counter their threats through countermagic they may not anticipate, and Get Lost as flexible removal for Cavern of Souls-proof creatures. Trim the burn-heavy interaction (Sear, Lightning Helix) since their life total matters less than their threats, and cut Improvisation Capstone as it's a win-more card in a grindy matchup where Cavern of Souls lets their creatures resolve unchecked. Play conservatively around their discard and lean on Day of Judgment to clean up any board states they develop.