Belcher is a fast combo deck aiming to cast Goblin Charbelcher off an empty or near-empty library for lethal, and Meltdown can proactively destroy their Goblin Charbelcher or Lotus Bloom before they can go off. Surgical Extraction can strip a key combo piece like Goblin Charbelcher from hand/library after they discard or reveal one, disrupting future draws of it. Practiced Offense and Ox of Agonas are far too slow against a deck that can kill on turn 1-3, so they're cut for proactive artifact disruption. This matchup is almost entirely about being faster than them or having a way to interact with their key artifacts before they combo off.