Sonic Epoch features SatAM Sonic in a time travel adventure as he is blasted 10 years into the future; a dark future where Dr. Robotnik has essentially won, and the very few remaining Knothole Freedom Fighters are barely clinging to life. Sonic arrives to reinvigorate the world and perhaps still be able to fight back the evil Doctor and hopefully somehow get back to his own time. The GBA version was a revival of the cancelled PC version. While the GBA version is "finished", it was a rush job, more for the sake of filling the gap of the previous version's incomplete status, and did not completely honor all aspects of the original story.