This is long but very interesting:

Holy crap man, 102 minutes. I started watching it, and the guy talks... very... slowly.... I bet if he had a little more energy that video would be 30 minutes.

I may come back later to watch that, thanks for sharing. I used to do some Doom mapping when I was in college, and my experimentation with Quake3 maps is actually documented on the CK site. I'm kind of interested to see what this is all about.

Just put it on x2 speed man

I think you'll find it even more interesting considering you've done some Doom mapping yourself!

I ended up watching this and yea, it is actually pretty interesting. 2x speed is a bit fast for me to follow, but 1.5x was perfect. Lots of things in that I didn't think were possible (like floors on top of floors, the noclip hell, the death level, etc etc) and the dark maze is a bit insane. Very cool though. I wonder how long that took to build.

Yeah, part of me also wonders to what extent the mod is actually that cool or deep and to what extent it's just the youtuber projecting his view/interpretation on it, but it's clearly still a pretty amazing achievement regardless of it.

The more pressing question is: why would anyone with the talent to mod the Doom engine this thoroughly bother with modding the Doom engine in the first place.

Oh, it was open-sourced years ago, so it's an interesting way to learn and stretch your programming skills. I could see the interest. But not for me. I prefer creating my own things, not building on the things of others. Still, that seems like how much of the open source community operates, and I applaud it. Maybe some day I'll actually get involved in some open source project. Well, one where I made the decision and wasn't mandated to do so by my (now former) employer.

BTW... this guy didn't mod the engine. He just used existing mods to build a ridiculous level, in case there was any confusion.