The comet approached Mobius fifty years ago, and Black Doom contacted Professor Gerald Robotnik and aided him Project Shadow, with Doom planning to use Shadow the Hedgehog as an agent. The comet departed soon thereafter, and while on its return trip to Mobius the Black Arms ran afoul of the Xorda, another alien race with its own claim on Mobius. The two races began warring, with the Black Comet currently in orbit around the ravaged Argentium. (StH: #169, #170, #171; CSE)
- The events of the comics in both continuities seem to indicate that the Black Arms are capable of steering their comet home worlds to some degree, as the Black Comet did not simply return to Mobius/Sonic's World 50 years after Shadow's creation as it seemed to do in the Shadow the Hedgehog game.