Along with their new installers for each classic game, they have a big Unreal Tournament 2004 patch in preview with overhauled Linux and macOS support. While none of these are supported by Epic Games directly any more, they did give their blessing to the OldUnreal team to continue updating them.
You can find their new full installers for Linux on their GitHub page for Unreal Gold, Unreal Tournament: GOTY and Unreal Tournament 2004.
It's especially interesting for Unreal Tournament 2004 because this is the newest game they're going to be providing patches for, with a "UT2004 Patch 3374 - Preview 9" now available from the GitHub announcement:
Hi everyone! Thank you for your patience. This is a preview of our 3374 patch. It has gone through internal testing and is relatively stable. It works in online games, except on servers with AntiTCC. We will release a new, 3374-compatible version of AntiTCC soon to address this issue.
Please note that this is the first public patch for Unreal Tournament 2004 in over 20 years. We have implemented numerous fixes and improvements, written a new SDL backend for Linux and macOS, and even a new renderer. We have also migrated the entire codebase to modern build systems. Some new bugs may have slipped in!
Here's shots of Unreal Tournament 2004 running on Linux with the new version:




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