Doom in Half-Life
Doom OST: E1M1 - At Doom's Gate
e1m1 midi file converted to hltas and running HL set up as close to Doom as I could.
Classic joystick movement. Note that I could only use +attack2 while the script was executing the "slot2" music.
e1m1.hltas https://pastebin.com/eqtUW6qN
doom.cfg https://pastebin.com/4D7wUR99