There's an old debate on whether or not Doom is just a fancy ray caster game, that it's simply a beefed up version of the Wolfenstein 3D engine. True, however, this is what Doom may have looked like if it was built using only the original Wolfenstein 3D engine, in this case the Raycasting Game Maker engine has been used.
This was the final test build made in March 2019 before releasing the first episode. The major difference is the enemy sprites/animations are much more final in the release version than what is shown in the video. The Doom 64 Sprites were basically place holder until there was time to custom render them. The Bull Demon sprite didn't change though. It was pretty much how I expected it from the first time I imported it into RGM.