Sonic 3 Unlocked is a work-in-progress modification of Sonic the Hedgehog 3 for the Sega Mega Drive. No stable releases have been made available as of writing -- download and build at your own risk.
The final version is expected to include:
- Additional playable characters and stages
- Encore Mode (from Sonic Mania Plus)
- Unlockables and optional collectibles
- Various fixes and quality-of-life improvements