Ep 13. Season 2, Episode 13

When a Pod lands in Knothole, Sonic and Sally realize the Doomsday Machine is already in operation. The Freedom Fighter groups break into the Doomsday Machine, only to find Robotnik let them in. Sonic tries to destroy the control room but is thwarted and almost roboti-sized. Uncle Chuck suggests they use the Power Stones to overcome Robotnik and, with Nicole's help, Sonic finds Robotnik's Power Stone.