UT2004 is now free, easily installable on Linux Mac and Windows thanks to OldUnreal! This is even officially endorsed by Epic, so totally legit.
I just ran through the Linux install in less than 2 minutes. The download was very fast, no issues encountered.
You can use the install script here: https://raw.githubusercontent.com/OldUnreal/FullGameInstallers/master/Linux/install-ut2004.sh
Just mark it executable, and run with ./install-ut2004.sh -d /path/to/install (wherever you want)
UT99 (Game of the Year Edition aka GOTY), the original UnrealTournament is also available and has been for a little while.
https://github.com/OldUnreal/FullGameInstallers/tree/master/Linux
This is very exciting, and incredibly cool to see. I bought the Editor’s Choice box set back in the day and this was one of the first big box games I owned with native Linux support.