- You may be looking for the Archie Comics Sonic the Hedgehog version of Silver's future, 3437 P.X.E..
In this future, Iblis had devastated the planet for two centuries after the "Iblis Trigger" released it at the time of Princess Elise's death. Despite many attempts to destroy Iblis, Silver and Blaze were unable to and as such went back through time to kill the "Iblis Trigger". The future was presumably changed for the worse when Mephiles the Dark fused with Iblis to become Solaris. However, when Elise and Sonic went back through time to extinguish the flame that would become Solaris, the future was changed yet again.
Although the future had changed, it had not changed much. Instead of Iblis, the world had been destroyed by the Ifrit, who had been released by Eggman Nega. Silver once again headed back through time to change the future, and after confronting Eggman Nega in the Ifrit's dimension (which, according to Silver, greatly resembled his own future), the Ifrit and Eggman Nega were sealed away within that dimension, presumably altering the future for the better.
In the DS version of Sonic Colors, Silver returns to Sonic's time, stating that the future is much better than the present, meaning that the future had been saved.
In the Archie comics
Due to the treachery of one of the Legendary Freedom Fighters, they were all destroyed and Silver's future was doomed without them. According to Silver, his universe could be described as "Pockets of civilization struggling against a global sea that seems to have a grudge." Due to the dire situation in his universe, Silver was driven to go back in time and through other dimensions repeatedly to find the traitor and save his future. (StH: #194, #195, #196, #215, #216, SU: #5, #6, #8)
Despite his efforts, however, Silver has yet to successfully deduce who the traitor is, and all his actions in the past don't change the future as a whole, but rather some aspects of it, up to the point where he considers himself lucky that anyone there remembers him at all.
- Silver's future at Mobius Encyclopedia, the Archie Sonic wiki