Colorless Prison/Ramp has no creatures for our discard spells to find value against early and wins with artifact-based lock pieces and giant threats like Emrakul, the Aeons Torn, so Collective Brutality's -2/-2 and discard modes are largely dead. Surgical Extraction can proactively remove a copy of The One Ring or another key artifact from their deck once we see it via Thoughtseize, limiting their ability to rebuy it. This is a race matchup where Thoughtseize and Unmask should target their mana acceleration (Ancient Tomb effects aren't discardable, but Karn, the Great Creator and The One Ring are) to slow their lock pieces. Our reanimated threats like Griselbrand and Atraxa are largely unanswered by their colorless removal-light suite, so keep pressure on.