People on protondb claim to have success running that using Luxtorpeda. Also id software released the source code for the game so you could just run a native Linux build with OpenGL support: https://uhexen2.sourceforge.net/. Source: about 1 year ago

I also wanted to throw in the link for the command line thing I mentioned https://uhexen2.sourceforge.net/ it's in section 1.3 but I'm genuinely not sure how to use it or what a command line even is lol I've also tried console commands but with no luck. I hope this helps! Source: over 1 year ago

My best friend and I have been meaning to experience this game for a while now but we can't seem to connect to each other. We are installing from http://uhexen2.sourceforge.net/ windows 64bit version. Source: over 1 year ago

I wouldn't bother running it on the original executable, just use Hammer of Thyrion. It's an updated source port. Source: about 2 years ago

On http://unrealworld.fi/ in the forums for example. Source: about 1 year ago

The obvious candidates have been mentioned, so check out http://unrealworld.fi. It's a massively detailed Iron Age survival sim. Perhaps you prefer something set in the modern age but in terms of simulation depth and realism I don't think there's anything comparable. Source: over 1 year ago

UnReal World has been in development since 1992. Source: about 2 years ago

Here's a brutal hardcore survival game: Unreal World Http://unrealworld.fi/. Source: almost 3 years ago