Sonic Chaos (May 17, 1993 prototype) - Hidden Palace

A prototype of Sonic Chaos (also known as Sonic & Tails in Japan) for the Sega Game Gear.

Sonic The Hedgehog Compilations - Every Sonic Collection Before

Proto:Sonic Chaos (Game Gear)/May 17, 1993 - The Cutting Room Floor

Sonic The Hedgehog Series (Alternate Timeline)

Sonic Chaos (May 17, 1993 prototype)

Proto:Sonic Chaos (Game Gear)/May 17, 1993 - The Cutting Room Floor

Sonic Chaos (May 17, 1993 prototype) - Hidden Palace

Sonic Prototypes (released by Hidden Palace)

Sonic Chaos (May 17, 1993 prototype) - Walkthrough

Early Sonic 3 prototype found, features major differences to the

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A brief history of Sonic The Hedgehog on PC

Sonic The Hedgehog Compilations - Every Sonic Collection Before

Sonic Chaos (Game Gear prototype; 1993-05-17) - Sonic Retro

The Hidden Palace Prototype Collection : Free Software : Free