Transformers: Beast Machines
The Maximals are back on Cybertron, but have lost their memories of the Beast Wars saga. In addition, they are infected by a virus that prevents them from transforming back to their robot forms; it also reverted trans-metals Optimus, Cheetor, Rattrap and Black Arachnia back to their original forms. They are also being hunted by the mindless Vehicon drones. Finding the Oracle underneath the city, the Maximals are turned into techno-organics to survive the virus; now they must master their emotions in order to transform again. The Maximals soon learn that Megatron got free mid-flight during their time travel back to the future, ending up there long before they showed up; he conquered the planet.