As time was being restored during Sonic X Shadow Generations, Mephiles the Dark manages to slip through to himself to the timeline to destroy the ones responsible for his downfall in the erased timeline: Sonic the Hedgehog, Shadow the Hedgehog, & Silver the Hedgehog. Sonic, Shadow, Silver, & their friends & allies speed off to bring an end to Mephiles' rampage through time and remove him from the timeline for good. But as they face Mephiles every time, they regain their memories from the erased timeline.
