Proto:Sonic the Hedgehog 3 - The Cutting Room Floor

The 1990 Tokyo Toy Show and beyond — unearthing new Sonic the Hedgehog pre-release evidence – MegaBites

Sonic & Knuckles (prototype; 1994-06-06) - Sonic Retro

Proto:Sonic the Hedgehog (Genesis) - The Cutting Room Floor

Proto:Sonic Heroes/E3 2003 prototype - The Cutting Room Floor

Sonic the Hedgehog (Prototype) LOST BITS Altered & Unused Content [TetraBitGaming]

Sonic's Edusoft: Leaked! - Unseen64

Sonic The Hedgehog [STI Concept / Proto] - Unseen64

Sonic Adventure Cutting Room Floor - Colaboratory

Why Sonic Adventure 2 Has My Favorite Gaming Soundtrack Of All Time