Editing Sonic the Hedgehog 4: Episode III (lost build of cancelled

Sonic Origins Plus Review (Switch)

Editing Sonic the Hedgehog (lost build of cancelled Sega CD port of Sega Genesis platformer; 1992) - The Lost Media Wiki

Could Sonic's Movie Redesign Be a Bad Idea? - Cheat Code Central

Editing Super Sonic (lost build of cancelled Sega CD port of Sega Genesis platformer Sonic the Hedgehog 2; existence unconfirmed; 1992-1993) - The Lost Media Wiki

Editing Sonic The Hedgehog: Awakening (lost build of cancelled Sonic the Hedgehog game; existence unconfirmed; late 2000s) - The Lost Media Wiki

Sonic Boom - Rotten Tomatoes

Sonic 4 Episode 3 Was Cancelled?

Editing Super Sonic (lost build of cancelled Sega CD port of Sega Genesis platformer Sonic the Hedgehog 2; existence unconfirmed; 1992-1993) - The Lost Media Wiki

So apparently, before being canceled, Sonic 4 Episode 3 was planned to be made by Sega Studios Australia and they asked Whitehead if he was interested in joining the dev. team : r/SonicTheHedgehog

Editing Super Sonic (lost build of cancelled Sega CD port of Sega Genesis platformer Sonic the Hedgehog 2; existence unconfirmed; 1992-1993) - The Lost Media Wiki

Sonic The Hedgehog 2 Review

Editing Sonic Runners (found endless runner mobile game; 2015) - The Lost Media Wiki

Sonic Team Developed Games - Giant Bomb

Sonic the Hedgehog CD (Video Game) - TV Tropes