I had a wonderful wholesome little adventure yesterday.
So, it so happens that I wrote a game design book. It sold well, so I wrote another. That other book has a companion in the form of a monographs of an old open world adventure/RPG game called "Gothic".
"Gothic" is a classic, it plays well even today, and also has a notoriously obsolete UI (designed before it was obvious that mouse is for camera controls). So overall a very interesting case study.