Not much is known about Sideways other than he works for Unicron. It is unknown if he was forced to work for Unicron or was made by him. He was sent to earth to monitor the Autobots and Decepticons war and retrieve their mini-cons. He first appeared in episode 15 of the Transformers Armada anime, he just teleported to earth and took the form of a purple motorcycle with his min-cons Rook & Crosswise disguised as his driver. He watched as Hot Shot with the star saber battle Scavenger and defeat him. After the battle Optimus asked him to reveal himself as he did he Transformed and used his Mini-Con Rook as his head to be a Autobot. He then told him his name and said he was a drifter who wandered into their conflict.
He was able to fool everybody into thinking he was on their side until he and Hot Shot when to the Decepticon base on the moon. He stroke a deal with Megatron that he would pretend to be Megatron's hostage and in exchange, no matter what, Hot Shot would turn over the Star Saber sword. At first, Hot Shot did follow through, but renegad at the last moment by calling the Mini-Cons back to him. Sideways suddenly attacked Hot Shot, knocking the Star Saber out of his hands and kicking it to Starscream. He switched his Mini-Con Rook with Crosswise, revealing his allegiance to the Decepticons. After sending Hot Shot back to his base beaten Sideways was able to convince them of his loyalty he began manipulating them and playing them against each other to suit his mysterious goals. One of these goals was the replacement of Megatron as Decepticon leader after a series of significant losses. Sideways sowed the seeds of rebellion within the Decepticon ranks, subtly turning Starscream against Megatron and convincing Megatron of Starscream's imminent treachery. The situation came to a head when the two Decepticons fought outside their base, but Sideways then realized Megatron would never execute Starscream for his insubordination, exposing an ever-constant weakness within the Decepticon command structure. After the battle, Sideways mused that this weakness would come back to haunt Megatron one day, and would be his ruin. Fortunately though, this incident somehow served to solidify the Decepticons as a unit, giving them much greater morale and cohesiveness, and achieving Sideways' aims of giving neither faction in the conflict a clear advantage.
Shortly there after Sideways tried to Hack the Autobot computer only to run into the children watching the battle between the Autobots and Decepticons on the monitor. He decided to transport them to a digital universe where he forced them into handing over their Mini-Con friends Grindor, High Wire, and Sure Shock. Soon they discovered that Sideways was only a illusion, and couldn't harm him. After he failed he began apologizing to an unseen entity which was revealed to be Unicron. Unicron then appeared and began chasing the children until they escaped. Soon the other Decepticons began to distrust Sideways suspecting he was not what he seemed, and realized he was manipulating them. He was soon discovered by Thrust communicating with his unseen master and Decepticons began attacking him. He tried to escape but was confronted by Megatron and cut in half by the Star Saber. They then discovered he was still alive and reattached himself after being attacked again only to absorb their blasts. Megatron, in fury and disgust, hacked Sideways to pieces and he was seemingly destroyed... or so they thought. Sideways had entered trans-phase mode. rising in the form of a twisted nanite creature before the Decepticons' eyes, declaring that the Star Saber and Skyboom Shield were merely toys to him, as he was near-invincible. He said there were millions of Mini-Cons left to be found, and challenged Megatron to see who would find them first, before flying off to parts unknown. After escaping he continued to watch the Autobots and Decepticon war and intervene a few times to tilt the balance like revealing the Requiem Blaster to the Autobots. He than begun to convince Thrust to side with him so that he could obtain the Star Saber, Skyboom Shield, and Requiem Blaster to revive Unicron. Once on Cybertron Thrust finally finished his but during the battle between Unicron, and Autobots & Deceptcions he secretly betrayed him and let him get killed by Unicron later. When Optimus and Megatron made thier way inside Unicron Sideways was their to greet them and revealed he was a puppet used by Unicron. He then sealed them away as he began his destruction of Cybertron. Shortly after the Kids were able to break Optimus and Megatron free. Seeing them Escape Unicron sent Sideways after them to destroy them before they ruined his plans only to be killed by the Optimus with the Requiem Blaster. With Sideways dead they were able to finish off Unicron for good.
Sideways was revealed to be still alive. It was revealed he was sustained by the dark powers of Unicron, and after two decades was able to return. Just he had no memories of what transpired before due to the Black Hole created by Unicrons destruction. He then began his old ways by being a double agent in the Autobot Decepticon wars. After a while he began aiding Starscream in helping him overthrow Megatron. After helping them locate the final Planet Key he revealed his story, and true intentions to them. Sideways was an inhabitant of the mysterious world known as Planet X, a planet of warmongering conquerors who crushed all worlds that stood in their way. Their reign of terror in the galaxy came to an end eons ago when they crossed paths with the people of Gigantion, whose Cyber Planet Key powers made their world a formidable opponent by enlarging the planet and its inhabitants to giant size, therefore being able to fend off the massive Planet X armies. The inhabitants of Planet X saw no option but to unleash their most powerful weapon, but in do so, they destroyed their own world, as well. The survivors were scattered across the galaxy, until the time came that only Sideways and one other, Soundwave, were the only known survivors of the race. Seeking revenge against Gigantion for its role in the destruction of their home, Sideways and Soundwave had allied themselves with Unicron - hence, Sideways's role in the war over the Mini-Cons. Now, with Unicron destroyed, Sideways had turned his attention to enacting revenge once more, and sought the power of the Cyber Planet Keys to accomplish it. Soundwave, meanwhile, had been seeing to the resurrection of Unicron, and with that goal accomplished, joined with Sideways on Gigantion. When Starscream and Megatron - now Galvatron - engaged in their final duel for control of the Omega Lock and Cyber Planet Keys, Sideways and Soundwave attempted to intervene, but the resultant energies released sundered reality and blasted them both, along with Starscream, into another dimension. In the final episode of the series a montage sequence shows Sideways and Soundwave on Planet X once more. Presumably, in the dimension they had been sent to, they were able to find that universe's version of Planet X and return to their home.
Sideways was very different than normal cybertronians. He was able to transform and use Mini-Cons like most of the other cybertronians but he also was able to teleport to different locations. He was also invulnerable to attacks and could heal from his wounds even if he was sliced into many pieces. He could also interact with machines using his mind or entering computers to hack into systems.
Other Series Appearances
Transformers: Revenge of the Fallen (2009)
Sideways will appear in the Sequel to Transformers he is able to transform into a Audi R8. His role has become very minimal compared to his anime couterpart. In the film he is a simple courier for the Decepticons who avoids combat and hides behind his larger Teammates when caught in battles. He is first seen in movie in China with Demolishor being attacked by Nest and the Autobots. He seen running away from Arcee and her sisters. After avoiding them he is confronted by Sideswipe who he has a rivalry with. After being caught by the four Autobots and Nest soldiers he makes a desperate attempt to escape by firing and reverting back to his vehicle form. While escaping Sideswipe jumps above and throws his blade in to his hood. He then grabs his blade and pulls it back cutting sideways in half.