Originating from the destroyed Planet X, Sideways witnessed his world's annihilation eons ago when its inhabitants unleashed their ultimate weapon against Gigantion. This catastrophe scattered survivors across the galaxy, leaving Sideways and Soundwave as the last known remnants of their civilization. Driven by burning vengeance against Gigantion for its role in Planet X's destruction, Sideways initially aligned with Unicron to pursue his goals. After Unicron's defeat and the subsequent collapse of the black hole, Sideways resurfaced two decades later with fragmented memories. Freed from Unicron's direct influence, his personality shifted; he adopted a more laid-back and flippant demeanor, often listening to and singing music during downtime, and formed a genuine friendship with Soundwave. However, discussions of their mission to avenge Planet X could trigger an abrupt return to grim seriousness. Operating as a faction-switching agent, Sideways manipulated the conflict between Autobots and Decepticons. He specifically targeted Starscream, who lacked memories of the Unicron Battles, covertly guiding him towards obtaining the Omega Lock and Cyber Planet Keys. Sideways intended to harness Primus's power through these artifacts to exact revenge on Gigantion. Soundwave, focused on resurrecting Unicron, eventually joined him on Gigantion for this shared objective. In combat, Sideways transformed into a jet plane and possessed innate flight capability regardless of form. He wielded a shield integrated into his left arm structure and demonstrated considerable speed and reflexes, enabling him to effectively dodge attacks while closing distance with opponents. He employed ambush tactics and, alongside Soundwave, engaged multiple Autobots simultaneously during the conflict on Gigantion. Sideways's efforts culminated during the final duel between Starscream and Galvatron for control of the Omega Lock and Cyber Planet Keys. Attempting to intervene, Sideways and Soundwave were caught in a massive energy release. This event sundered reality, blasting them alongside Starscream into an alternate dimension. A subsequent montage depicted Sideways and Soundwave back on Planet X.