Sonic the Hedgehog 4 goes episodic this summer - GameSpot

Project Needlemouse revealed as side-scrolling sequel to speedster's original Genesis trilogy; Episode 1 confirmed for Wii, Xbox 360, PS3.
Sonic is back for his fourth installment in the classic 2D series, revamped from the ground up.

Sonic 4 Episode 1 » SEGAbits - #1 Source for SEGA News

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Editing Sonic the Hedgehog 2006 (lost build of Tokyo Toy Show tech

Needlemouse Revealed!!!

Sonic 4 Is 2D and Episodic