Nice topic, to bad the answer is : nothing.

Teleglitch reminds me Quake a bit, mostly in style. 

Must be the pixelly graphics and the brown palette. 

To be fair, I did actually think about the question but came to the conclusion that no game was similar in gameplay post ~2000 so it seems pointless to talk about it.

Teleglitch is so completely different gameplay wise. 

 

Not unless you can justify them. But Q3A certainly don't. 

Unreal, despite the completely different moods, comes close at times. But despite the AI, the combat there is mostly horizontal. Yeah you pretty much run out of anything resembling Quake once you leave the 90s, or at least projects started in the 90s (such as Daikatana).

Quake 2 would be cheating, but it is the closest to having the vertical combat, (Flyers, Icarus, Technicians, the cave creatures jumping, Gunners above you dropping down grenades).

Blood at times was a little more vertical thanks to Gargoyles, Phantasms, and Cultists chucking dynamite...

This furthers my appreciation of Quake's excellence, even if it does sadden me with regard to other games. 

Remember, even back in 1996, no-one cared much for Quake's single player partly because it was completely and utterly overshadowed by the multiplayer. The FPS genre was now suddenly all about DEATHMATCH and FRAGS, and like a red-headed stepchild, Quake's single-player was swept aside and forgotten. If it was more of ~a big deal~ I think people would have cloned it.

The other thing that caused people to ignore Quake-style SP happened when Half-Life came along and suddenly after that it was just a push towards ever-increasing "realism", and arcadey fantasy FPS was never really seen again, apart from in SS and PK, games which fail to be like Quake for a number of obvious reasons. 

Was the closest. (though the gameplay was more like Wolf 3D).
https://www.youtube.com/watch?v=FjTnOFmVVW4

In all honesty I can't remember a single game that is really similar. I wouldn't compare Unreal to it at all, Unreal was quite a different experience IMO.

I actually would love to create a quake-like game in the indie-retro fashion that is quite popular these days. I'm sure if all the talented folk at Func and various places banded together we'd be able to make something crazy special. 

Really? Nobody else thought of that?

As to Quake's SP I always thought that that was what made it so great. Yeah, yeah DM was all the rage (see what I did there?) but honestly the bandwidth wasn't there for it except over a LAN. SP games are good because the game experience is universal to all players. Chithon throwing flaming fireballs is the same for everyone and the surprise of seeing that for the first time was a deal sealer. I bought the game that same day and have never looked back.

As far as I'm concerned Q3 really killed the franchise. I know that I stopped buying iD games (just because they were made by iD anyway) because of it, and to be quite honest I've not (so far) felt like I was missing something. Q2 was almost an afterthought with a hint of what Quake might have been.

Romero was Quake (the game, with some help of course). Carmack was the engine. Lose one or the other and it all falls apart. Carmack was still a genius but without each other they BOTH lost their way (see Daikatana and Doom 3).

Personally I'd go and buy a Doom I/II or Quake episode made by Romero even today. 

seems to share something in common with Quake, after I have read the review at:
http://www.electricescape.com/etherealhell/index.php/game-reviews/2009-reviews/item/necrovision 

Hehe Dooomer that's my review too. I actually did think about Necrovision, the second half is quite close to the fantasy style of Quake. But the first half in a crappy WW2 setting ruined it, and the gameplay wasn't that close. Necrovision gameplay is probably more like Painkiller (and Dreamkiller), that is having the same old enemy with guns or projectile like attacks over and over again, just with a different model or skin. No variety like Quake had.

Other than Necrovision, Enclave has a smidgen of Quake style, no surprise since a Q1/Q2 mapper created most of the levels. I suppose some of the Unreal Tournament games have levels that could be considered Quake's fantasy/sci-fi setting, but they're not Lovecraftian or hellish at all, and not SP so can't be considered.

That's about it from what I've played.

Actually the closest was probably that Doom3 mod that was a remake of a Quake level. Wish they did more than one level! 

Undying?

It had a few of the same elements, even though it was more about exposition and a slower style of play the actual movement and combat were pretty quick.... as I remember.

I also remember being disappointed by the art in Teleglitch. Usually I don't care about visuals, but in this case all the enemies looked the same, which killed it for me. 

Requiem: Avenging Angel was overloaded with various magic abilities to a similar degree as Undying, but it felt more aggressive and oldschool overall. Don't take my word for it though, I played it a long time ago. 

Heretic-Hexen-Rune-DN3D 

kingpin maybe? but maybe it felt that way since it was built on the q2 engine.