Sonic the Hedgehog (lost build of cancelled Amiga port of Sega

The CANCELLED Sonic 1 Port for Commodore Amiga : r/SonicTheHedgehog

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

The 'Sonic Killer' And More Console-like Amiga To Mega Drive Ports

Video Games – The Maurice Bear Times

Sonic The Hedgehog on the ZX Spectrum (either a mock-up or from a actual build of the game) : r/lostmedia

What caused the downfall of SEGA? - Quora

Sega Genesis: Most Up-to-Date Encyclopedia, News & Reviews

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

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-16 (non-existent build of unreleased Sega Genesis/Mega Drive game based on Sonic the Hedgehog animated TV series; 1993) - The Lost Media Wiki

Sonic Saturn (lost build of cancelled Sega Saturn prototype of platformer; mid-1990s) - The Lost Media Wiki