Silver

Silver the Hedgehog is a fourteen year old hedgehog who comes from at least two-hundred years in the future. He commonly travels through time to help Sonic and his friends. He has the ability to use psychokinesis, but unlike most characters from the Sonic series, he has no super speed. His voice actor used to be Pete Capella but now it is Quinton Flynn.

''Super Smash Bros. Brawl
Silver the Hedgehog made a cameo on the Green Hill Zone stage along with Tails and Knuckles. He also appears as a trophy and a sticker in the game.

''Mario & Sonic at the Olympic Games
He was originally supposed to appear in this game but was scrapped later on. A beta file of Silver was found on the European version.

''Mario & Sonic at the Olympic Winter Games
Silver appears in Mario & Sonic at the Olympic Winter Games as a skill type playable character. His signature move for the Wii version is Levitate and Teleport Dash for the DS.

''Mario & Sonic at the London 2012 Olympic Games
Silver makes his second playable appearance in the third installment of the Mario & Sonic series, Mario & Sonic at the London 2012 Olympic Games. He is once again, a Skill type.

Official Profile and Statistics
''Silver the Hedgehog is a new competitor for Team Sonic. Coming from the distant future with telekinetic abilities, Silver's signature moves are the Levitate ability on the Wii and DS and Teleport Dash ability on the DS. Expect the unexpected when this time-travelling hedgehog takes on the Olympic Winter Games.''

Official Profile
Coming from the distant future with telekinetic abilities, expect the unexpected from Silver when this time-travelling hedgehog takes on the London Olympic Games!

Trivia

 * Silver's appearance in Sonic Rivals is not mentioned in Super Smash Bros. Brawl, even though his appearance in Sonic The Hedgehog 2006 is mentioned.