Sonic the Hedgehog (Prototype) - Hidden Palace

A prototype of Sonic the Hedgehog for the Sega Mega Drive.

Sonic the Hedgehog 2 (Simon Wai prototype)/Comparisons/Hidden Palace Zone - Sonic Retro

Sonic 1 prototype found!

Hidden Palace Zone - Sonic Retro

Sonic the Hedgehog (Prototype) - Hidden Palace

Sonic CD - Wikipedia

Sega Genesis / 32X - Sonic the Hedgehog 2 (Prototypes) - Hidden Palace Zone (Dry) - The Spriters Resource

Sonic the Hedgehog (Prototype) : r/Roms

Sonic the Hedgehog 3 (Nov 3, 1993 prototype) - Hidden Palace

Sonic the Hedgehog 2 - Wikipedia

7 Sonic The Hedgehog Prototypes You Were Never Meant To Play

Sonic the Hedgehog 2's Proto Palace Level Discovered: How to Unlock it, with Hands-On Video

Sega Genesis / 32X - Sonic the Hedgehog 2 (Prototypes) - The Spriters Resource

Sonic Hacking Contest :: The SHC2022 Contest :: Sonic the Hedgehog Vintage - 2022 Demonstration :: By ZachmanAwesomeness

Sonic the Hedgehog prototype - Labyrinth Zone by SonicDash57 on DeviantArt

They did it, Hidden Palace did it. : r/SonicTheHedgehog