Be in 1st place in ether Babylon Story or Sonic Story. I forgot which one it is.
you need to beat the game to unlock them
Silver is not in Sonic Riders. However, he is unlockable in Sonic Riders: Zero Gravity by completing the Babylon story.
you can not but you can unlock super sonic
Beat Babylon Story.
You beat heroes mode on story
Shadow - Beat Heroes story
yes you can unlock Cosmo in sonic riders zero gravity you cant get cosmo in sonic zero gravity riders for Nintendo wii. the characters you can get are sonic, tails, knuckles, jet, wave, storm, silver, blaze, knights, shadow, Amy, eggman, rouge, cream, billy hatcher, amigo, SCR-GP, and SCR-HD.
Same with NiGHTS and Billy Hatcher. Complete all the missions
Shadow is unlocked by completing the Hero Story;Silver, complete Babylon Story.
Really Easy, you unlock SCR-HD in free race after you have beaten the Babylon storyYou unlock SCR-GP by beating the Babylon Story
Complete all missions to unlock Ulala, Aiai and Nights. For Sonic Riders: Zero Gravity, complete all missions to unlock Nights, Amigo and I think Billy Hatcher, I have them unlocked I just haven't played the game in ages.
Only play with SCR-GP once time im granprix mode to unlock it. but it's not confirmed yet By Phill07 "Aurora's Gueto"