Update - 2016/07/16: See here for Keen 5!
Here's a fully-playable, 16-color enhancement for the original Commander Keen IV- Secret of the Oracle (CGA version), with code patched + graphics redrawn and reworked to support CGA's composite output capabilities.
Why, you ask? - just because I wanted to brush up on some skillz... and because John Carmack said that he never knew it could be done.
- Download the patch (315 KB) - more info in the included readme
- Video: running in DOSBox
- Video: running on real hardware (The Oldskool PC)
- A copy of Commander Keen IV: Secret of the Oracle, v1.4-CGA, Apogee release. This can be downloaded here (thanks keropi).
The executable should have this size and date stamp: KEEN4C.EXE 98,007 01-Feb-92
- DOS 3.3+
- 8088 or higher (runs fine at 4.77MHz, but rather slow)
- ~540 KB of free RAM
- A true IBM CGA card driving a composite monitor or TV
Or, you could just try it out in DOSBox. I highly recommend a current SVN snapshot, patched with reenigne's latest composite CGA improvements (plus the updated experimental PC speaker patch, if you want authentic SFX).
These patches may need some manual editing for applying to current SVN, but if you're on Windows, you can use my pre-baked build based on SVN-r3980 with the two patches applied (this is what I used to record the video).