There is an old DOS program called Power 3D, more widely know as Pie GCS, made by Pie in the Sky Software. It works perfectly in DOSBox-0.63 for Windows. I'm going home tonight to try it out on DOSbox-0.61 on my Linux box. GCS stands for Game Creation Software. It's an old 3D game engine that makes games similar to Doom. Actually it's power lies somewhere between Wolfenstien 3D and Doom. Well, I recently found a free download of the old DOS GCS at Do not link to abandonware. It's an abandonware site. If anyone is interested in creating old DOS style FPS games with a very easy to use program, check it out. Do not link to abandonware