About
Sonic 3 & Knuckles is the 1994 combined Mega Drive / Genesis platformer formed by locking the Sonic & Knuckles cartridge onto Sonic the Hedgehog 3, widely regarded as the high watermark of the classic 2D Sonic era.
Sonic 3 A.I.R. (Angel Island Revisited) is an unofficial enhanced PC port developed by Eukaryot using the Oxygen Engine, transforming the original game data into a modern experience with widescreen rendering, 60 FPS throughout, a competitive split-screen multiplayer mode, a full Time Attack feature, comprehensive bug fixes, and an extensible mod system. The project ships no game data and requires the player to supply their own Sonic 3 & Knuckles ROM (the standalone Steam release was delisted in May 2022; the SEGA Mega Drive & Genesis Classics collection followed in December 2024).
Identity
Launch
- Binary
- sonic3air_linux
- Needs files
-
- Compatible Sonic 3 & Knuckles ROM — supply your own copy (e.g. from the Steam SEGA Mega Drive & Genesis Classics version you already own); copied in via the in-app installer on first launch
Runtime
- Runs as
- Native Linux
- Proton
- not needed
⚙ Setup notes
Port: Sonic 3 A.I.R. (Angel Island Revisited) is an unofficial enhanced PC port of Sonic 3 & Knuckles, developed by Eukaryot (Christian Stadler) using the custom Oxygen Engine.
Proton: A native Linux binary is available directly from sonic3air.org and runs on Steam Deck without Proton.
Features: The engine provides widescreen rendering, a Time Attack mode, competitive split-screen multiplayer, numerous bug fixes, and a full mod support framework.
DRM: S3AIR is engine-only and ships no game data — a compatible Sonic 3 & Knuckles ROM supplies all content, copied in via the in-app installer on first launch. The official site recommends the ROM from the Steam SEGA Mega Drive & Genesis Classics version of S3&K. The standalone S3&K title was delisted from Steam in May 2022 (the wider Genesis Classics collection followed in December 2024), so the game is no longer purchasable there — use a copy you already own.
Install: Extract sonic3air_game.tar.gz from sonic3air.org and add the sonic3air_linux binary (or the bundled sonic3air launcher script) as a non-Steam game in Desktop Mode.
Controller: Controller support works out of the box (no Steam Input remap required); the Deck gamepad is detected natively.
The one thing to know
Supply your own copy: sonic3air.org provides the engine binary only and ships no game data — players must supply a compatible Sonic 3 & Knuckles ROM they already own (the official site recommends the Steam SEGA Mega Drive & Genesis Classics version). The standalone S3&K Steam title was delisted in May 2022 and the full Genesis Classics collection in December 2024, so it is no longer purchasable. The in-app installer copies the ROM into place on first launch.
Proton: Use the native Linux binary on Deck (type = 'native', no Proton). Add sonic3air_linux as a non-Steam game.
Features: Widescreen, Time Attack, and competitive split-screen multiplayer are all available out of the box. The mod system is fully functional on Linux.
Community guides
Write-ups and threads from people who got this (or a similar) game running. deckport links to them — it doesn't reproduce them.
Get the artwork
deckport never hosts game images. Open this game on SteamGridDB, pick
the cover / hero / logo / icon you like, and drop them into the
game folder under .deckport-art/ before you push it to the
Deck. The importer files them under the right names automatically.
Run it on your Deck
Two files: the one-time importer (deckport.py) in your
Deck's home folder, and this game's install helper. Copy the game
into ~/Games and run the helper with Steam closed — it
writes the recipe (binary, launch options)
and registers the shortcut with artwork.