While on an information gathering mission in Robotropolis, Sally discovers that a train is leaving for the western part of the continent. Eager to stop it, Sally boards the train. NICOLE scolds her for going on an adventure without backup, but Sally tells her that Rotor is tracking them and is probably organizing the Freedom Fighters to assist them. The group realizes the train is probably carrying the Dynamac-3000, Robotnik's latest super robot, and boards their plane to join up with Sally while Sonic runs ahead. Sally finds Dynamac and attempts to scan it, but is subdued by a mysterious figure. Sonic reaches the train, but is shot down by its defense systems.