As the leader of the Autobots, Prime headed up their mission to search for new sources of energy to revitalize the depleted Cybertron. Optimus vowed to Elita that he would return from his mission for her, but just before the launch of the Ark, Optimus was mistakenly led to believe that Elita was killed. Shortly after its launch, the Autobots' craft was attacked by the Decepticons' space cruiser, the "Nemesis", and boarded by Megatron and the Decepticons. In the ensuing struggle, the G-forces of a nearby planet pulled both craft down, and the Autobots' ship crashed into a volcano, thrusting all the occupants into emergency stasis. Four million years later, in the Earth year 1984, a volcanic eruption jarred the ship's computer, Teletraan I, back to life. The computer reactivated the Decepticons, programming them with new Earth-based disguise modes. As a parting gesture, Starscream fired upon the Autobot ship, creating a landslide. The vibrations from that landslide knocked Prime into the path of the computer's restoration beam, restoring him to life, thus beginning the war anew on Earth.