In Season 2 episode War Dawn, we learn that Optimus Prime was originally known as Orion Pax. He worked for Alpha Trion as a Cybertronian historian/librarian, and lived with his girlfriend, Ariel. The young Autobot was intrigued by the talk of power and insurrection spoken by Megatron. But when Megatron seriously injured Orion Pax and Ariel, and killed Pax's best friend, Deion, OP saw the truth behind the Decepticon way of life - Lies, cruelty, and treachery.
Alpha Trion rebuilt Orion Pax and Ariel into Optimus Prime and Elita-One, and gave Optimus the Autobot Matrix of Leadership, declaring him the leader of the Autobots, charged with the task of holding down the evil Decepticons.
As Optimus Prime, OP is the consummate leader; he never raises his voice at his troops, never threatens them with an ultimatum, and will never ask his soldiers to do something he isn't willing to do, himself.
In Transformers: The Movie, Optimus leads the backup team of Autobots during the Decepticons' assault on Autobot City. He engages in a final battle with Megatron, exclaiming "One shall stand; One shall fall," finally sick of the Decepticons' reign of tyranny over their homeworld of Cybertron. At the end of the battle, Prime has Megatron defeated, until interference from Hot Rod turns the tables in Megatron's favor. Megatron blasts Prime in the Transformers equivalent of vital organs, felling Prime to his knees. With Megatron proclaiming, "It's over, Prime," Optimus manages to get in one last blow, proclaiming, "NEVER!" Megatron is knocked off a ledge, falling over a hundred feet. Seeing his foe finally defeated, Prime collapses.
Shortly after, Perceptor proclaims that OP's wounds are fatal, and the Autobots are unable to repair him. Before going where All Are One, Optimus passes the Matrix of Leadership to his old friend, Ultra Magnus, and informs the Autobots at his side that "One day, an Autobot will rise from our ranks, and unleash the power of the Matrix to light our darkest hour." With his final words, "Until that day... 'til all are one," Prime drops the Matrix (which is saved by Hot Rod and then handed to Magnus), Prime's head falls to the side, and his body greys out, indicating his death.
Optimus' essence had become one with the Matrix, and during Season 3 of The Transformers, he would occasionally guide Rodimus Prime (Hot Rod + the Matrix) through his troublesome adventures.
In the episode Dark Awakening, the Quintessons use what is left of OP's body to create a zombie who lures the Autobots into giving him the Matrix of Leadership. The Quintessons' intent was to lure the Matrix away from the Autobots, as it was too powerful a device for them to overcome. However, in the end, Optimus' good nature came through, and he saved his Autobot comrades, flying his ship towards a sun as he went offline yet again.
Return from the DeadEdit
In The Return of Optimus Prime Part 1, Optimus was discovered by scientists Jessica Morgan and Jeffry Swofford just before his ship flew into the sun. Despite Swofford's reluctance, Morgan convinced him to bring Prime's body back to Earth to examine it. While they were flying away spores from a nearby planetoid contaminated their own ship. On Earth, the scientists (and Jessica's father) found out that it created a contagious "Hate Plague," which the two male human scientists immediately decided to use as a way to end the threat of all Transformers, forever, using Optimus Prime's body as bait.
When nearly every being in the Universe is infected with the Hate Plague, Hot Rod sends Sky Lynx on a mission to recover a Quintesson to repair and rebuild Optimus Prime. At the end of the episode, the Quintesson succeeds and Optimus proclaims that now, "no force in the Universe can stop me."
In The Return of Optimus Prime Part 2, Optimus is filled in on the situation involving the Hate Plague by Kup, Sky Lynx, Jessica Morgan, Bumblebee (whom Prime re-dubs "Goldbug"), and the Quintesson. Jessica reveals that an alloy she and her father had been working on was seemingly impervious to the Hate Plague, as they were not infected while in their ship, which was coated in said alloy. However, the alloy had been stolen by the Decepticons in part 1. Optimus, Sky Lynx, Goldbug, and Jessica travel to the Decepticons' new homeworld of Chaar, where Galvatron is being hunted by his own soldiers. Prime reasons with Galvatron and explains that the metal alloy Galvy had stolen was the key to stopping the Hate Plague. Galvatron reluctantly agrees, and Optimus is coated in the alloy.
Optimus Prime then tracks down the now-infected Rodimus Prime in order to take back the Matrix of Leadership. Upon his eventual success, Optimus dives into the Matrix to find a cure for the Hate Plague; It is revealed that the Plague existed once before, and was contained in the star that exploded near Morgan & Swofford's ship, as nobody had the wisdom to cure it. With nothing left to try, Optimus unleashes the power of the Matrix as a last hope, and the wisdom contained within manages to cure the Hate Plague. However, doing so drains the Matrix of all its power.
In thanks for his help, Optimus lets Galvatron go, and, as he is once again commander of the Autobots, instructs them for the first time in years to "Transform, and roll out!"
Out of nowhere The Decepticons (ALL OF THEM) attack Autobot City on Earth, and they manage to steal the one thing Prime feared they were after: The Key to the Plasma Energy Chamber, a device which every Autobot has been charged with protecting (Unsurprisingly, Ultra Magnus has no clue of its existence. I guess he couldn't deal with that now, in Autobot school). He sends all the Autobots to Cybertron, hoping to stop Galvatron before it's too late.
But it was too late.
A bunch of stuff happens without Prime around, so the next time we see him, he's amazed that several Autobots have taken up Nebulan residents in their heads and as their weapons. But OP's cool, so he just rolls with it and they all team up to defeat Galvatron and Scorponok, and Cybertron is brought to a new Golden Age that Rodimus mentioned at the end of Transformers: The Movie.
And then the cartoon was cancelled, so we have no idea what happens next.
Power Master Optimus PrimeEdit
Released in 1988, Power Master Optimus Prime was the Americanized version of the character God Ginrai. But it's cool, because suddenly we had a new Optimus Prime toy, for the first time in four years. However, THIS version of Optimus could combine with his otherwise-useless trailer, and become a super-powered (and super-huge) robot!