New Sonic the Hedgehog (1991) prototype uncovered by preservation groups - Tails' Channel

A prototype of Sonic the Hedgehog (1991) was showcased by a video game preservation group in a New Year's Eve livestream.

Sonic the Hedgehog (1991 video game) - Wikipedia

New Sonic the Hedgehog (1991) prototype uncovered by preservation groups - Tails' Channel

Rare Sonic the Hedgehog prototypes unveiled for the first time - Tails' Channel

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Sonic the Hedgehog (1991) prototype discovered - The Independent Video Game Community

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