Grand Prix Mode
To unlock "Grand Prix" mode, play through and complete the "Hero" storyline mode. The Grand Prix mode becomes playable immediately after your progress is saved.
Mission Mode
Play through and complete the "Babylon" and/or "Hero" storyline mode to unlock the "Mission" mode. This mode becomes playable when you play through the storyline mode you completed for the second time. Mission mode uses the same levels as in the storyline mode, but there are special objectives added.
Easy Rings
After you have unlocked "Mission Mode," begin playing the second mission. The object of mission 2 is to collect as many rings as possible, and there is no limit to how many you can acquire. Complete mission 2 and wait for the results screen to appear. This screen tells you how many rings you have collected and sends all the rings you collected into your ring account. The game doesn't send you a notification of the transfer, but it does take place. If you keep restarting the mission after you hit the score screen, you can easily get over 1,000 rings credited to your ring account in an hour or less.
Unlockable Characters
Play through the "Hero" storyline mode and complete it to unlock "Shadow The Hedgehog," "Rogue The Bat" and "Cream The Rabbit." Beat the "Babylon" storyline mode to unlock "Silver," "Blaze," "SCR-GP" and "Eggman." Complete every mission in the storyline mode to unlock "Billy," "Nights" and "Amigo." Race and beat SCR-HD in a "Free Race" to unlock "SCR-HD."