[mrandish]

Fabien's site is an invaluable resource, but I think I've read it all over the years and he one has post specifically on Commander Keen, and that's focused on just the adaptive tile refresh (https://fabiensanglard.net/ega/). This book is 211 pages on the entire game.

On the first page this author credits Fabian's excellent analysis of Doom and Wolfenstein as the inspiration to attempt the same for Commander Keen.

> "Fast forward to 2021, I discovered Fabien Sanglard’s website and began reading his Game Engine Black Books on Wolfenstein 3D and Doom. Inspired by those works, I wondered whether I could do something similar for Commander Keen: open up the source code, ex plore the files, and piece together a picture of the overall architecture and the clever tricks used. The style, dimensions, and structure of this book are intentionally similar to Fabien’s Game Engine Black Books, as an homage to those masterpieces."

Just skimming so far, but this book looks like a valuable contribution to the genre of retro game code analysis. Obviously, it will build on the work of others who've done adjacent research. In a page 87 footnote the author refers readers to Fabien's site for detailed instructions on installing a DOSBox and Borland C++ dev environment.