Sonic3AndKnucklesRecomp

Sonic 3 & Knuckles — Recompiled

Play Sonic 3 & Knuckles on your PC, with Sonic, Tails and Knuckles. Optional mods bring in more adventures and let Mighty and Shadow join the fun. Separate versions of Sonic 3 and Sonic & Knuckles are also available.

Download and play

1. Download your game's package from Releases. Choose Sonic3KRecomp for the combined game and the extra campaign options.
2. Extract the complete Windows ZIP, then open the game. On Linux, make the AppImage executable and open it.
3. Select your own matching game ROM in the launcher.
4. Check your controls, then select PLAY.

Game files are not included. The combined game needs a Sonic 3 & Knuckles ROM; the separate versions need their corresponding ROMs. The latest release, v0.6.0, has Windows x64 ZIPs and Linux x86_64 AppImages for all three games.

The extra campaigns, Mighty and Shadow shown below are included in v0.6.0 as experimental, off-by-default options in Sonic3KRecomp.

Every zone, across the campaigns

The combined campaign brings together 46 zones, including the final boss areas. These are actual Sonic3KRecomp captures, mixing Sonic, Tails, Knuckles, Mighty and Shadow, including their Tails pairings. Imported stages use S3K movement and abilities. Extra campaigns and characters are experimental and require your own supported game inputs.

Campaign order	Zones	Content
Sonic the Hedgehog	7	19 acts, including Final Zone
Sonic the Hedgehog 2	11	20 acts, through Death Egg
Sonic CD	7	70 act/time variants; Present, Past, Good Future and Bad Future
Sonic 3 & Knuckles	14	Both original campaigns, through The Doomsday
Sonic Megamix v3	7	19 acts, including Final Fight

Expand a game to see every zone. Sonic 3 and Sonic & Knuckles have separate galleries below. Screenshots use 16:9 widescreen, except The Doomsday, which is shown at native aspect because its widescreen player rendering needs a fix. CD captions identify the time period pictured.

Sonic the Hedgehog — all 7 zones

Green Hill · Marble · Spring Yard · Labyrinth · Star Light · Scrap Brain · Final Zone.

Sonic the Hedgehog 2 — all 11 zones

Emerald Hill · Chemical Plant · Aquatic Ruin · Casino Night · Hill Top · Mystic Cave · Oil Ocean · Metropolis · Sky Chase · Wing Fortress · Death Egg.

Sonic CD — all 7 zones, sampling all four time periods

Palmtree Panic · Collision Chaos · Tidal Tempest · Quartz Quadrant · Wacky Workbench · Stardust Speedway · Metallic Madness.

Sonic the Hedgehog 3 — all 6 zones

Angel Island · Hydrocity · Marble Garden · Carnival Night · IceCap · Launch Base.

Sonic & Knuckles — all 8 zones

Mushroom Hill · Flying Battery · Sandopolis · Lava Reef · Hidden Palace · Sky Sanctuary · Death Egg · The Doomsday.

Sonic Megamix v3 — all 7 zones

Sunny Shores · Dark Fortress · City Outskirts · Misty Maze · Starry Night · Metallic Base · Final Fight.

Extra campaigns and characters

In Sonic3KRecomp, open Mods to choose your additions. Each has its own checkbox, and all are experimental and off by default.

Mod	What you need
Sonic 1 stages	Your own supported Sonic 1 ROM and a prepared stage pack
Sonic 2 stages	Your own supported Sonic 2 ROM and a prepared stage pack
Sonic CD stages	Your own supported Sonic CD (US) disc image
Sonic Megamix stages	Your own Sonic Megamix v3 ROM and a prepared content pack
Mighty	The same Megamix ROM and content pack
Shadow	The same Megamix ROM and content pack

Enable whichever campaigns you want. They play in this order: Sonic 1 → Sonic 2 → Sonic CD → Sonic 3 & Knuckles → Megamix. You can enable Mighty or Shadow without enabling Megamix stages. Selecting the Megamix files once fills them in for all three options.

For Sonic CD, select your disc under the mod's Files and wait for the import to finish before pressing PLAY. No Sega CD BIOS is needed for this mod. It uses Sonic 3 & Knuckles' characters and abilities. For the original Sonic CD experience, see SonicCDRecomp.

Stage packs must be prepared from your own game files before use. Follow the Sonic 1/2 setup guide, Megamix setup guide, or Sonic CD setup guide. The CD import currently also needs Python and Pillow, as explained in its guide.

Make it your own

• Controls: set up your keyboard or controller in the launcher.
• Widescreen: enable Mods → Widescreen and choose Adaptive to fit the game to your window, or select a fixed screen shape.
• Knuckles & Knuckles: enable the mod and play as Knuckles with a crowd following you. Choose 1–74 extras; additional local controllers can join in. Available in Sonic 3 & Knuckles and Sonic & Knuckles.

Your progress

Use the game's normal save slots to keep your progress. When upgrading or moving the game, keep all your save files and settings together. Disabling an extra campaign or character keeps its progress for when you enable it again.

With extra campaign mods enabled, save states, rewind and online play are currently unavailable. Use the normal in-game saves instead.

Help and feedback

These optional campaigns and characters are still experimental. If something goes wrong, report an issue with your game version, enabled mods and a screenshot if possible.

Want to build or contribute? See the build guide and release guide.

Credits and license

Sonic and the original games belong to SEGA. Campaign and character additions build on Sonic Anthology by sonsegajp (formerly SonicTrilogy), whose Sonic 1, Sonic 2 and Sonic CD work is adapted here with attribution, and on Sonic Megamix by Team Megamix. This project uses segagenesisrecomp. Project code is under the PolyForm Noncommercial license; third-party notices accompany the downloads.

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