One of the my favorite story lines from the original
Generation One series was the
Return of Optimus Prime story which began in
Dark Awakening and continued in
The Return of Optimus Prime (Part 1 and 2). Prime's return was only slated to be a one shot comeback in
Dark Awakening, but due to the backlash of his death in the movie, Hasbro ordered his return to the animated series. Thus, one of the largest retcons in the original series took place.
In Dark Awakening, Optimus Prime was found in an orbital space mausoleum where his shattered body had been placed to rest forever following his final battle with Megatron. Rodimus Prime and his team sought refuge there after being chased by Galvatron and the Decepticons in deep space. Rodimus learns that Optimus is indeed alive and saves them from Galvatron. Optimus was still heavily damaged and didn't know how he came back online. Prime unexpectedly betrays the Autobots, and leaves them to die as the mausoleum is sent on a collision course with that system's sun. Optimus then returns to Cybertron to lead the Autobots into a trap set by the Quintessons to destroy them all and retake Cybertron. Rodimus Prime and his team are able to intercept Optimus Prime and the Autobot fleet. Rodimus Prime learns that Optimus' body was taken by the Quintessons and brought back on line to do their bidding. Rodimus battles Optimus to the finish, and as Optimus prepares to destroy Rodimus, his old personality resurfaces. Optimus Prime returns the Matrix to Rodimus Prime, and then Optimus sacrifices himself in order to save the Autobots and defeat the Quintessons. This was supposed to be the true, heroic end of Optimus Prime. Ultra Magnus declared that the nova from the explosion would be his memorial, and Rodimus closed the episode saying, "I may never be the leader that you were, but for sure, I'm gonna try. So long...Prime."
Optimus returns in the season three finale called The Return of Optimus Prime (Part 1 and 2). This is where the largest retcon occurs in order to bring him back. Optimus Prime had lost an arm, half of his face, and his body was heavily damaged at the end of Dark Awakening. In The Return of Optimus Prime: Part 1, his body is intact and brand new. In this episode, there were also no signs of the Quintessons, no Autobots, and Optimus Prime was dead...again. Prime was still alive in Dark Awakening until the ship was destroyed. Also, Prime's ship was different than the one he was piloting in the last episode. Also, none of the Autobots seemed to remember the Quintessons plot, except that Rodimus remarks that they had revived Optimus Prime once before. Overall, it was a blatant attempt to force Optimus Prime back into the Generation One universe (and the start of a series tradition in each series as the Prime always dies and returns). After this, Optimus Prime would take command once again and lead the Autobots until the end of the series. In the Japanese exclusive Transformers: Headmasters, he would in fact die again to save Cybertron.
Don't get me wrong, I loved The Return of Optimus Prime (Part 1 and 2). The animation was top notch, great music, and it had a pretty good story. However looking back on this episode over twenty plus years since it aired, it was filled with continuity errors and issues. Plus, the concept was kind of random. Dark Awakening is definitely the better episode, although I wish it could have been produced later to take advantage of the better animation and music. Had the writers of The Return of Optimus Prime taken better care, this "trilogy" could have been even greater.