Omnispeak is an open-source reimplementation of Commander Keen episodes 4, 5, and 6. It aims to be a pixel-perfect, bug-for-bug clone of the original games, and is compatible with savegames from the DOS version.
It's written in modern C99/C++ and is compatible with both Windows and Linux.
Omnispeak requires a computer with OpenGL 2.0 support
You can download binaries for linux here or for windows here. These downloads include Keen 4 already set up for you.
You can also check out the source code on github: https://github.com/sulix/omnispeak.Installation
To play, you'll need to include files from the original game.
Omnispeak supports:
- Keen 4 v1.4 EGA
- Keen 5 v1.4 EGA
- Keen 6 v1.4 EGA
- Keen 6 v1.5 EGA
You'll need to take the following files from your version of Keen, and place them in the same directory as the 'omnispeak' binary:
- GAMEMAPS.CK?
- EGAGRAPH.CK?
- AUDIO.CK?
You'll also need the files from the 'data' directory corresponding to your version of Keen.
To run the game, simply switch to the directory with the data files, and run:
./omnispeak
You can provide Omnispeak the following command-line arguments:
- /EPISODE <4,5,6,6v14,6v15>
- Runs the given episode/version of Commander Keen
- /FULLSCREEN
- Starts the game in fullscreen mode
- /FILLED
- Starts the game with aspect-ratio correction off.
- /NOBORDER
- Starts the game with EGA overscan border emulation off.
- /NOJOYS
- Disables Joystick detection.
- /DEMOFILE <filename>
- Plays the demo recorded with Keen's F10+D cheat in filename.
Known Issues
- Modding support is not implemented.
- Mouse / Gamepad support is not implemented.
- Joystick support is new and very buggy.
- Some debug cheats (notably demo recording) are not supported.
- New settings ("Fullscreen", "Aspect Ratio", "Overscan border" are not saved.
- The game always redraws everything every frame.
- Some chunks are not cached properly at load time (doors, especially)
- No fallbacks for systems without GLSL and non-power-of-two texture support.
Links and Thanks
Omnispeak is brought to you by David Gow, NY00123, and lemm.
More thanks go to adurdin, John Hodge and the entire Commander Keen fan community, who are keeping Keen alive. And, of course, none of this would be possible without Keen's original creators, thank you!


