Silver the Hedgehog

Silver the Hedgehog is a character from the Sonic the Hedgehog and Sonic Universe series, who originates from the future. Silver is usually the one to travel back in time in order to right some wrong in the timeline. Compared to the other Sonic characters, he's a bit green around the gills and still needs help determining what the right thing to do is, but he compensates with a strong sense of justice and impressive psychokinetic powers.

Pre-Worlds Collide
Silver arrived from the future in hopes of discovering who betrayed the Freedom Fighters, and thus, doomed the time period he's from.

While working with the Secret Freedom Fighters, he found that it was the roboticized Sally Acorn (now referred to as Mecha Sally), and sought to help both Team Fighters and the Arctic Freedom Fighters to save her. During the fight, he managed to disable her. Silver was estatic he'd finally saved his future, but before more could be done, the Genesis Wave was activated. (Sonic the Hedgehog #247/FCBD 2013)

Worlds Collide
After the Genesis Wave occurred, Silver met up with Sonic shortly after Sonic had sent Team Chaotix to investigate the disappearances of Knuckles, Tails, Shadow, and Amy. However, Silver eventually ended up captured by Copy Robot in front of Sonic. (Sonic Universe #51)

Silver was then turned by Doctors Eggman and Wily into the Roboticized Master, Silver Man. His Special Weapon was Psycho Burst. He, alongside most of the Roboticized Masters save for the Chaotix, was later dispatched to attack Proto Man in the Skull Egg Zone. (Sonic the Hedgehog #249)

Silver Man, alongside Blaze Woman, later ambushed Sonic and Mega Man just as they were about to scale invisible blocks. Silver Man was able to land a hit on Mega Man with his Psycho Burst, although not without being hit by Mega Man's Sonic Blast at the same time. His identity reasserted, Silver then proceeded to hold Blaze Woman at bay just as she was about to roast Sonic alive with her Fire Tornado while Mega Man stopped her with the Sonic Blast. Although thankful for Sonic and Mega Man restoring them, Silver declined to help, due to being too exhausted from the whole ordeal. (Mega Man #26)

Silver aided Mega Man, Sonic and the rest of their friends in fighting off an army of Robot Masters. He did well in fighting off most of them with his psychic abilities only to be taken by surprise by Flash Man (who upon noticing his fur was jealous of him having too much hair). Though he escaped and continued helping the others. (Sonic the Hedgehog #250)

Eventually Silver and the rest of his allies were aided by Dr. Light's Robot Masters, though the entire team was caught up in the Super Genesis Wave. It was, however, reversed by Sonic and Mega Man (both of whom achieved super transformations). (Sonic the Hedgehog #251)

Post-Worlds Collide
Due to Dr. Eggman interfering with Sonic's attempt to restore their world, history was altered. One change noticed is that Silver hadn't been seen since helping Sonic and Tails to save The Wisps (as depicted in the game Sonic Colors). (Sonic the Hedgehog #252). He is the only one amongst the group that didn't appear since the wave or known if he still has his memories of the old timeline. He later reappeared (Sonic Universe 75), where he was closing all the genesis portals to other dimensions and worlds. Silver is set to appear in Worlds Unite.

Pre-Worlds Unite
Silver is altered to a new problem known as the Genesis Portals by Professor Von Schlemmer and travels back in time on several occasions to close them up. (FCBD 2015)

During his second trip back in time, both he and Metal Sonic end up within a different portal. Both of which send them to unknown, alternate worlds. (Sonic Universe #75) It is later revealed that Silver somehow managed to end up in 21XX of Mega Man X's world, more specifically right at Sigma's base during the Maverick Hunter's final stand against Sigma. He managed to subdue Vile with his powers, and proceeded to inform them of the Genesis Portals, including that Sigma went through one. He then identified the area Sigma went to, although due to a mix-up, Mega Man X, Zero, and Axl ended up going to an alternate universe from the intended one.