Omega Supreme was originally a Guardian - one of the giant robots, based on the designs of the Quintessons' Dark Guardians, created to guard the cities on Cybertron. It was Omega's job to guard Crystal City, the most beautiful of all the cities. Omega was close friends with the robots known as the Constructicons, and did his job well, until the evil Decepticon, Megatron used a device known as the Robo-Smasher on the benevolent Constructicons, warping their minds and making them malicious and evil. Their first act as Decepticons, as per Megatron's command, was to destroy Crystal City. They lured their "good friend" Omega away from the city, and then demolished it. Omega was infuriated, and turned on the Constructicons, but they merged into their gestalt form of Devastator for the first time, and held Omega as the Robo-Smasher tried to reprogram him too. However, Omega broke free and destroyed the Robo-Smasher. He forsook emotion, rationing that if his friendship with the Constructicons had resulted in this betrayal, then all emotions as a whole were bad. It is presumed that he spent the four million years that Optimus Prime, Megatron, and their forces were trapped, deactivated in the Ark, on Earth, hunting down the Constructicons. When he discovered they had joined Megatron on Earth, he arrived to join the Autobots and continue his quest for revenge. Prime learned of Omega's history with Constructicons when Omega was sent to destroy an asteroid heading towards Earth. He destroyed the asteroid, but a monstrous alien emerged from within it. However, Omega attacked the Constructicons, rather than stop the alien. Prime tried to teach Omega that there was more to life than revenge, but all Omega could say was "Possibly".

Omega Supreme is portrayed as the third-tallest Autobot, under Metroplex and Fortress Maximus respectively. He possesses the ability to transform his body into three separate forms at once - a rocket, capable of interstellar flight, as well as that within Earth's atmosphere, a launching pad for said rocket, and a laser cannon tank, which serves as a defensive mechanism for the launching pad. In robot mode, he can fire bolts of energy from the plasma blaster in place of his left hand, as well as from the three-fingered claw which makes up his right hand. The barrel from his tank mode, positioned on the rear of his head, may also be used in robot mode. His armoured hide is comparatively resistant to conventional artillery, as he is commonly able to dispatch his enemies before they can do him serious damage. However, the electrum-protected Decepticons were able to make short work of Omega (Ref: "The Golden Lagoon").

Omega Supreme's final fate is unknown. He was not present at the Autobot City Massacre (although if he had been, the results for the Autobots may have been better), and was seen but once during 2006. It is presumed he continues to seek out the Constructicons, whose fates also remain unknown, to quench his thirst for revenge.