Cities are de-fuzzed by dropping crystals in the path of fuzzed people, turning them back into civilians. Some civilians will also be carrying crystals (the info map shows how many crystals are present in a city). Civilians are turned into fuzzed people when touched by a fuzzed person. If Agent USA is touched by a fuzzed person, it will drop the player's crystal inventory by half, rounded up. If touched while carrying none, Agent USA turns into an uncontrollable fuzzed person who will wander around aimlessly and board trains to different cities until he touches a crystal. Fuzzed people may also enter from a nearby contaminated city via train.