Sonic 3 Unlocked has a downloadable Sonic Hacking Contest demo, adding Amy Rose, Mighty the Armadillo and Ray the Flying Squirrel to Sonic the Hedgehog 3 on Mega Drive. Developer Liliam announced its availability on 23rd October 2026, with the contest listing providing a 4 MB download.
The modification also adapts Encore Mode from Sonic Mania Plus, bringing a remixed adventure and a changing team of characters to Sonic 3. It remains a demo, with several planned features absent and known collision problems documented by its creator.
Liliam began work on the project in February 2018. Its public repository documents an effort spanning more than eight years before this demo, bringing ideas from later classic-style Sonic games into the Mega Drive original.
The expanded cast draws on abilities from Sonic Origins and Sonic Mania. Liliam credits MainMemory with converting Sonic’s Drop Dash into Mega Drive assembly, and Rubberduckycooly with decompiling Ray’s Air Glide before Liliam adapted it for the older console.
Amy’s sprites come from Sonic Origins Plus, while Mighty and Ray draw on Sonic Mania Plus. Liliam reduced the colours to fit the Mega Drive palette and created additional poses and animations, including new Super Sonic artwork.
Other artists contributed particular elements. Delta Conduit supplied the large ending sprites for Mighty and Ray, while E-122 Psi created Amy’s extra-life icon and end-sign artwork. The project also acknowledges Sonic 3 Complete and Sonic 3: Angel Island Revisited as inspirations.
Encore Mode is present, with more work planned
Encore Mode keeps its progress separately from the regular single-player game and uses a team of characters. Its characters share one 15-colour palette, which Liliam notes changes their appearance compared with the standard mode.
The demo does not yet include the alternate level palettes planned for Encore Mode. It also retains Sonic 3’s existing Special Stage layouts. Original layouts, revised item distribution and relocated Special Stage rings are among the changes intended for the finished version.
A Museum option is another unfinished part of the project. Liliam’s repository discusses further major versions as the remaining features are completed, without assigning a final release date.
The current build includes cutscene and score-countdown skipping, additional animations, changes to scripted sequences and numerous fixes. Its music includes tracks drawn from the 3rd November 1993 Sonic 3 prototype, whose preservation by Hidden Palace receives a credit. The project uses Flamedriver, flamewing’s revised version of the Sonic 3 sound driver.
Liliam lists two specific collision issues in the contest notes. Amy and Tails sometimes catch on scenery because of their shorter rolling height, while Knuckles’ climbing stops when he touches a solid object. A different solution for the latter is planned.
The Sonic Hacking Contest entry hosts the demo and its release notes. Liliam’s public repository provides further project information and a place to report bugs.
