Now when the Sonic Hedgehog series are trademarked by Sega, wait for something new.
Sonic Unleashed has raised a lot of questions and rumors lately. Some of them can be answered or proved right now.
Dr. Eggman returns as the primary antagonist for Sonic Unleashed. In this installment, he has managed to shatter the world into pieces, and it is up to Sonic to return the seven broken continents back to normal by retrieving the Chaos Emeralds and activating their power. Sonic's progress is made even more difficult by his (as-yet unexplained) contraction of lycanthropy, turning him into a werewolf at night.
A day-and-night system will also be introduced, and this may well tie into Sonic's werewolf form.
Gameplay will primarily consist of two modes: a 3D sidescroller, with two-dimensional gameplay (as found in the Sonic Rivals series), with seamless shifts to 3D, on-rails gameplay, as found in the recent Sonic and the Secret Rings.
The game is currently being developed by Sega's development teams from Japan , the United States , and Europe in an attempt to reinvent the franchise. The game will be a multiplatform release on the PlayStation 2 and PlayStation 3, the Xbox 360, and the Wii.
The game runs on Sega's Hedgehog Engine, which has been in development for three years.