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The Sonic Hacking Contest 2026 has officially kicked off, which can mean one thing and one thing only: a bunch of exciting new Sonic ROM hacks are about to hit your newsfeeds.
Understandably, given the number of projects that have been released, I haven't yet had an opportunity to dive into absolutely everything, but I was particularly excited to see that a demo has now been released for Sonic 3 Unlocked.
This is an extensive modification of Sonic the Hedgehog 3 for the Sega Mega Drive / Genesis classic, from the programmer Lilliam, which aims to bring "concepts from modern-day 'classic' Sonic titles back into the Mega Drive original.
This includes introducing popular playable characters from Sonic Mania & Sonic Origins (like Amy Rose, Mighty the Armadillo and Ray the Flying Squirrel), implementing Sonic Mania Plus's Encore Mode (allowing you to play a remixed version of the original game as a growing group of characters that you can switch between with the press of a button), and incorporating bug fixes, quality-of-life features, and secrets (from cutscene skips to unlockable abilities).
As Lilliam notes, they took the sprites for Amy, Mighty and Ray from Sonic Origins Plus and Sonic Mania, but they had to colour-reduce them in order to fit the Mega Drive palette, and also ended up coming up with some original animations for the characters here and there, such as new poses for Super Sonic. Some artwork and music were taken from the original game, and there are also credits on the main submission page for other individuals whose artwork either appears (Delta Conduit, E-122 Psi) or who were influential in other ways. For instance, there is a specific shout-out for the teams behind Sonic 3 Complete and Sonic 3: Angel Island Revisited, which Sonic 3 Unlocked is "very obviously" inspired by.
Right now, as Lilliam notes, the demo that is available is just a taste of what's to come. The alternate level palettes for Encore Mode are not available yet, as they weren't completed in time for the demo, and they plan on introducing further changes to the finished version, such as adding original Special Stages and rebalancing monitors. There's also talk of a museum available from the main menu (more details apparently coming soon), and even more features planned for the future.
You can download the demo of the hack here, to give it a spin yourself.