Rocky & Bullwinkle

Rocky and Bullwinkle must stop the evil Boris and Natasha from robbing a train full of priceless valuables. While Boris uses the "Upsidasium" to float the valuables to Natasha's waiting helicopter, Rocky must fly around and intercept them. Once Rocky catches the valuables, he gives them to Bullwinkle for safekeeping. The 2600 version of Rocky & Bullwinkle was actually developed before the Intellivision version, not the other way around as was usually the case. Although Rocky & Bullwinkle was complete and had passed quality assurance, it was cancelled for unknown reasons. The Intellivision version was still to be released, but Mattel closed its doors before it could be completed.