You can run Doom inside (DOS) Doom, for real.

I have found a code execution exploit in the original DOS Doom 2 and ported a Chocolate Doom to it. And then Chocolate Heretic. Attention: This does only work on the original DOS Doom2 version, no GZDoom or other source ports. This is a good thing as you don’t want code execution exploit on modern systems. People would abuse it to spread malicious code. DOS version is available on Steam and you can use DosBox emulator to run it. Copy to the directory where you have and then in DosBox start it with command “doom2 -file “. (Copy other files too if you want to try them. Game injection has to be renamed to ) Release: Source code: