Sonic the Hedgehog and friends inadvertantly stumble into Maginary World. They discover that villain "Void" has shattered the Master Precioustone, resulting in chaos around the world. Lumina Flowlight is counting on Sonic's friends to save Maginary World.
- Sonic the Hedgehog
- Miles "Tails" Prower
- Knuckles the Echidna
- Amy Rose
- Big the Cat
- E-102 Gamma
- Super Sonic
Doctor Robotnik also makes an appearance.
A loose adaptation of the game appeared in Issue 251 of Sonic the Comic Online. Lumina summons Sonic to the Maginary Zone in order to fight The Void. However, in Necropolis, Sonic is made to battle Turbo and loses. Sonic's failure gives The Void the advantage in "The Universe Game" but the two hedgehogs personally intervene, causing Lumina to sacrifice the galaxy. Sonic comes up with the plan to just thump The Void, ending the war.
The previous game in the series was Sonic Pocket Adventure. The next is Sonic Adventure 2.