Mystic Forge Combo assembles a critical-mass artifact engine with The One Ring, Karn, the Great Creator, and Mystic Forge, so Surgical Extraction gives us a way to strip their copies of a key spell once one is in a graveyard. It needs a card already in a graveyard to name, so it works best on a spent card like Transmute Artifact or Kozilek's Command, exiling the remaining copies from their hand and library. Unmask is cut since it's tempo-negative against a deck that can rebuild via Urza's Saga and multiple artifact tutors, and Koma is far too slow against their mana-ramp shell built around Ancient Tomb and Urza's lands. The extra Collective Brutality can only take an instant or sorcery from their hand, so its discard mode hits Kozilek's Command or Transmute Artifact, and it can't touch artifacts or planeswalkers like Mystic Forge, The One Ring, or Karn. It also drains 2 life, which helps in the race. Lead with Thoughtseize and Cabal Therapy to disrupt their hand before they assemble the Mystic Forge or resolve Karn.