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.
I call this video the Pre-Alpha Version because it was footage from the first time I imported the Doom 64 graphics into RGM. I didn't end up keeping a copy of this raw-looking sprite version, alas. In some ways, I like this version the most and wish I still had a build of it. It was like the moment I chucked in the basic Doom type graphics into RGM it instantly became some deformed version of Doom-- it felt Doomy straight away.