The Quintessons eventually developped 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.
Prior to the Great Exodus, the Quintessons became a peaceful race and dissolved their empire. Optimus Prime eventually made contact with them on Quintessa and the Quintessons offered to serve as a neutral third-party in Autobot-Decepticon peace talks. The lead Quintesson, the Curator, who spoke with Prime apologized for the crimes of his ancestors and claimed that to redeem his race he would do everything he could to end the Cybertronian Civil War to hopefully make peace between their two peoples.
Capturing the Nemesis in a tractor beam above their planet. they forced Megatron and Starscream down to the surface to discuss peace. In doing so they exposed to the Decepticons that they had vast Energon reserves. The Curator opened the peace talks saying that violence solved nothing and offered Optimus and Megatron both the chance to speak without interruptions from the other. However, while the talks progressed Starscream led his troops to collect the Energon. Optimus had anticipated this and placed his troops to guard it. The result was a massive firefight and explosion that ravaged Quintessa.
Both Autobot and Decepticon stole as much of the intact Energon as they could and returned to their ships. As the Ark left, Optimus expressed deep regret for what had happened to the Quintessons and noted that recent events presented historical irony but may have also destroyed any chance of peace with the Quintessons. The Nemesis left soon after, following the Decepticon theft of the tractor beam.
- 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, conquer through either brute force or subtle means and use slave labor. The differences are that Daleks are cyborgs whereas Quintessons are purely mechanical, also the Quintessons eventually became peaceful which the Daleks are incapable of.