UBG Reanimator wants to discard Griselbrand, Atraxa, or Archon of Cruelty via Faithless Looting and bring them back cheaply with Reanimate, Animate Dead, or Shallow Grave, so Surgical Extraction can proactively remove their reanimation targets from the graveyard before they can be brought back, or strip a card they've already discarded. Force of Negation gives us a free way to stop a key Reanimate or Animate Dead resolving on their turn when we're tapped out. We trim some of our weaker tempo tools since the matchup is a race against their explosive graveyard plan, and our own clock from Dragon's Rage Channeler and Murktide Regent needs to come down fast enough to beat a reanimated Atraxa or Griselbrand.