The Black Arms invaded and many were lost. Until a hedgehog named Jules stood up to Black Doom and defeated him, but died in the process. Now the remaining Black Arms are forced to live in sanctuaries, kept under watch, and treated harshly. Doom's two sons, Shadow and Eclipse, are forced to pay for the crimes of their father. Meanwhile, Sonic and Silver, the two sons of Jules, are training in the GUN program. Both want to make sure history doesn't repeat itself. But Shadow grows tired of the mistreatment. And vows to do something about it...