He is, in "his" own words, "a first generation product of Vector Sigma ," meaning that he was one of the first wave of robots created by the Quintessons and imbued with life by the mega-computer when the aliens occupied Cybertron twelve million years ago. Then known as A-3, he spearheaded the rebellion of the consumer goods robots, turning their 'slave brand' into a symbol of freedom. Due to an attempt by a Quintesson in the year 2006 to alter history, A-3 was temporarily transported to the future, while a group of Autobots travelled back to his time and helped in the pre-arranged attack on the Quintesson city. A-3 returned in time to activate the Coder Remote device hidden within his slave brand, deactivating the Quintessons' Dark Guardians and turning the tide of the war. Eventually, the Quintessons were forced off the planet, and an age of peace began... but it was not to last.
The consumer goods robot renamed themselves the Autobots, but their product line brother, the military hardware robots, redubbed themselves Decepticons, and, lusting for power, began a civil war. The Autobots developed transformation to fight back with stealth (and it's also possible that they used the Quintessons' Dark Guardians, reprogrammed as Guardian Robots to help), eventually ending, or at least stalemating the war, allowing the peaceful and prosperous period known as the Golden Age of Cybertron to begin. It is unknown if A-3 ever modified himself to transform.
But a viper lurked within this paradise - and soon, the Decepticons developed transformation technology as well, along with robot-mode flight powers, leading to the creation of Megatron . Megatron promptly killed the current Autobot leader, and Alpha Trion gained possession of the Autobot Matrix of Leadership , hiding it away until the next leader emerged. When Megatron attacked an energy warehouse, fatally injuring several young Autobots, including one named Orion Pax, the time-displaced Aerialbots searched for help - and they found A-3, now calling himself Alpha Trion. He had been working on a way to rebuild Autobots into configurations truly designed for battle, and was convinced to first employ it on Pax, who was rebuilt into Optimus Prime , to whom Alpha Trion gave the Matrix. He also rebuilt Pax's girlfriend, Ariel, into Elita One . It is suggested to be possible, though never confirmed, that Diode, Orion's best friend, was also one of Alpha Trion's rebuilt transformers, and thus is the former form of Ultra Magnus , or less popularly, Ironhide . Prime refers to both Magnus and Ironhide as old friends, but the identical design of Ultra Magnus's inner robot to Prime, and the fact that Ironhide is clearly characterised as being older than Prime, make Magnus the more popular choice.
Over the course of the next four million years, after Optimus Prime, Megatron and their troops were lost on Earth, Alpha Trion acted as a guide to Elita One's guerilla team of Female Autobots.
In the Earth year 1985, Elita One was captured by the Decepticons to lure Optimus Prime into a trap, but expended all her energy using her stasis powers to save Prime from death. Knowing that only Alpha Trion could save her, Prime searched for the ancient Autobot, who knew that only Optimus's power supply could properly interface with Elita's. It became apparent that even though Trion remembered his hand in Prime's creation, Prime himself lacked that knowledge.
A short time later, the Decepticons attacked Alpha Trion's workshop in search of the Key to Vector Sigma. Successfully obtaining it, Megatron used Vector Sigma to give life to his Stunticons as Trion led the Autobots into the depths of Cybertron. At Prime's suggestion, several Cybertronian shuttle craft were rebuilt to resemble Earth jets, to as a new team to combat the Stunticons. But without the key, Vector Sigma could not be activated, and so Alpha Trion, as the only being possessing the same computation Matrix as Vector Sigma, sacrificed himself to give life to these jets - the Aerialbots.
Trion merged with Vector Sigma, but also apparently coexisted both within the computer, and within the Matrix, as, in the Earth year 2006, when Optimus Prime entered the Matrix to search for a way to stop the Hate Plague , Alpha Trion was there to tell him that he knew nothing of a cure.
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