Twin Star

Twin Star is the group name for the diametrically-opposed planets Sperity and Toruin. Autobot Headmaster Highbrow likened them to heaven and hell - while Sperity is rich in energy, covered in glistening cities and populated by small robots (prosperity, y'see), Toruin is barren and lifeless, with nothing but rocky deserts on its surface (Toruin, you get it?). The two worlds, however, are connected by a massive tunnel-bridge that allows transit between them.

Twin Star may in fact be one of the lost Cybertronian colonies- its natives use the same Character model as the miners on the planet Master.

RTM dub name: The Twin Planets

Headmasters animated series
Aware of the massive amounts of energy on Sperity, Galvatron made it one of his targets during the Decepticons’ series of attacks on planets throughout the galaxy. Warnings and laser fire from the surface of Sperity did not to deter him, as Scorponok easily smashed through the planet’s defenses, only for their searches to turn up nothing more than a few loose energon cubes.

With the Autobot Headmasters on the Decepticons’ trail, Fortress elected to have Daniel Witwicky, Wheelie and Arcee relocate to Toruin, that they might remain safe in the coming battle. While on the planet, however, they discovered an underground city, and realised that the inhabitants of Sperity had used the tunnel-bridge to evacuate civilians and energy to Toruin. With this information relayed to them, the Autobots pulled out as the evacuation was completed and the tunnel-bridge disconnected from Toruin, allowing the planet to drift off through space. Unaware of the deception, Galvatron allowed Toruin to leave, believing there had never been any energy in the first place, and ended the campaign rather than be made to look a fool any further.