The Quintessons eventually developed space flight and sought out the home planet of their creator: Cybertron.
At some point they acquired the blueprints for Space Bridges, either from their creator's files or from another species they encountered.
When the Quintessons found Cybertron, they discovered that it was recovering from natural disasters. Due to this the Cybertronians were less advanced than they had anticipated and the Quintessons decided to conquer them. However, the Cybertronians were much more physically powerful than the Quintessons and thus they opted for a more subtle means of conquest.
They posed as a benelovent species and helped rebuild Cybertron. They planned to master Space Bridge technology and ship Cybertronians as slaves to their colonies and the rest of the galaxy.
Eventually the Cybertronians, led by Sentinel Zeta Prime, discovered what the Quintessons were planning and exiled them, stealing the Space Bridge specifications in the process. The Quintessons retreated back to their home world, never forgetting their humilationn at the hands of their former slaves, while most Cybertronians forgot they ever existed, due to poor records of their reign.
Prior to the Great Exodus, the Quintessons became a peaceful race and dissolved their empire, reforming their race into one that helped the "lower species" and strived to create a unified galaxy of peace. On the surface. In reality, they had become even more violent and manipulative after losing Cybertron. They conquered hundreds, possibly thousands, of other worlds either enslaving them, draining them for resources or adapting them to their own needs. They were particularly fond of puppet governements. Eventually they, discovered the Cybertronian colony Aquatron and conquered it. They eventually discovered that Cybertron itself had become non-functional due to civil war and began plotting to retake that world.
Somehow managing to construct a duplicate of the Matrix they began influencing Optimus Prime, causing him to unwittingly set the Ark for Aquatron. When the Autobots arrived the Quintesson Inquirata posed as the "Curator" and lied that Aquatron was simply a mechanical planet with no connections to Cybertron. While he and his men set a lavish reception for Prime, Jazz, Ironhide and Ratchet, other Quintessons abducted Kup, Rodimus and Bumblebee and implanted false memories that Optimus Prime was a tyrant who lived to subject all non-Cybertronians and was abusive to his men.
When Megatron and the Decepticons arrived eager for the kill, the Quintessons forced them to the surface. When an all out battle was about to break out, the Quintessons revealed who they were really were, prompting the Cybertronians to unite briefly and murder their enemies. Before this could happen the Quintessons claimed to be beings of peace and wanted to help end the war. Though no Cybertronian trusted the Quintessons, Prime and Megatron decided to play along until they knew what their foes were planning. The Curator decreed that the next day would hold Autobot/Decepticon peace talks.
Through individual manipulation of Prime, Megatron and Starscream, the Curator was able to set up a mock court. The Quintessons then accused the Cybertronians of rebelling against their true masters and creators. Using 'testimony' from the three brainwashed Autobots, they implicated the Prime and through further Matrix manipulation they almost broke him. Megatron of all bots came to Prime's defence. Having both lived through the Quintesson invasion of Cybertron, Megatron claimed that while he and his fellow miners fought off the Quintessons, bots like Orion did absolutely nothing and hid from the invaders. Spurred on Prime claimed that Cybertonians may have been influenced by the Quintessons but they were Primus' creations and reminded them that the Quintessons themselves had been created by a Cybertronian. Being reminded of their origins enraged them, but they maintained their composure and said they had judged them "innocent" which meant they woudl have a slow death by Sharkticon, while Prime and Megatron would duel to the death.
Harvesting the Energon leaked from the duel, they powered up a Space Bridge and sent a massive invasion force to Cybertron. However, the Cybertronians on Aquatron and Cybertron managed to fight off their enemies with the Curator being brutally murdered by one of his puppets. Though ravaged Aquatron was freed, the Ark took off for space while the Nemesis stayed behind to commence repairs.
Later, Optimus realized that they had never learned the exact location of Quintessa, meaning the Quintessons were still a threat and would return one day.
- The depiction of the Quintessons in the Aligned continuity family is similar to the Daleks from Doctor Who, specifically as they were shown in the TV21 comic series. Both species murdered their creator, are round in shape, have squid like features, conquer through either brute force or subtle means and use slave labor. The differences are that Quintessons are purely mechanical beings where as the Daleks are cyborgs, the Quintessons have emotions and individual personalities and the Daleks are individually powerful while Quintessons have zero fighting ability.
- The Quintessons may also be the "Creators" in the Transformers live action movies but it is currently unknown if they would make an appearance anytime soon. They were also the creators of the cybertronians in Generation 1.