Omnispeak — A Commander Keen Reimplementation

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

Keen 4 under Omnispeak
Keen 5 under Omnispeak
Keen 6 under Omnispeak

You can download binaries for linux here (v1.0) or for windows here (v1.0). These downloads include Keen 4 already set up for you.

You can also check out the source code on github:


To play, you'll need to include files from the original game.

Omnispeak supports:

These should be the easiest versions to get. For example, the Steam version and the (no longer available) 3DRealms version are both version 1.4. Keen 6 is not easily available, but you should be able to find patches which convert one version of the game to another. Keen 6 v1.5 fixes a few bugs, so it's probably best to use it if you can.

You'll need to take the following files from your version of Keen, and place them in the same directory as the 'omnispeak' binary:

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:


You can provide Omnispeak the following command-line arguments:

/EPISODE <4,5,6,6v14,6v15>
Runs the given episode/version of Commander Keen
Starts the game in fullscreen mode
Starts the game with aspect-ratio correction off.
Starts the game with EGA overscan border emulation off.
Disables Joystick detection.
/DEMOFILE <filename>
Plays the demo recorded with Keen's F10+D cheat in filename.

Known Issues

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!