Use WSAD to move, and click to shoot. Press C to show variable and press V to hide them again. There's no jumping yet, but I'm adding it, and it will be good-old teleporting like in the 2D platformer. #RiseofthePixel
Thanks to the Scratch Team for the basic Size 3D Effect code (I modified it a bit) and thanks to @eliasw for his little fps engine, which I scrutinized and used some of it to make this. Also, credit to @SpikePie for making the thumbnail. Finally, thanks to original Doom, I took some inspiration from it to make the gun design and some other bits of the game. Feel free to take the engine and do whatever, but ONLY the engine. Not the gun, the name, sprites, etc. No credit needed, as I said before, I got most of this from the Scratch Team. If anyone has any questions on how it works or wants to use it, just comment. I'll answer within a day. I changed the other sprite to a slime, made it so the sights turned red over the slime, added non-teleporting jump (will be changed), and added some more stuff to the gun.