Dimir Excruciator leans on discard (Duress), targeted removal (Bitter Triumph, Requiting Hex), and sweepers (Deadly Cover-Up, plus Day of Black Sun from their board), so a resilient threat like Surrak, Elusive Hunter is excellent. It can't be countered, so it gets past counterspells like Flashfreeze from their board, and it draws a card whenever Bitter Triumph or another opposing spell or ability targets it. Torpor Orb shuts off the enter triggers that drive their value plan: Deceit's bounce or discard, Seasoned Cryomancer's loot-and-stun, Uldaros Theorix's graveyard-copy trigger, and Overlord of the Balemurk's mill/return trigger when it is cast as a creature. It does not stop Overlord's attack trigger, and it does not stop Superior Spider-Man's Mind Swap, which is a choice as it enters rather than a triggered ability. Soul-Guide Lantern answers their graveyard synergies (Superior Spider-Man, Uldaros Theorix) proactively by exiling creature cards before they can be used. Earthbender Ascension and Shared Roots are too slow against their efficient removal and discard, and Esper Origins' surveil and life gain do little here compared with adding resilient threats. Keen-Eyed Curator stays in, since its ability to exile cards from graveyards is also relevant against their graveyard-based plan.