For the free Raytracing-enabled version of the classic shooter Quake 2, the update 1.8.0 has been released for Linux on Steam:

Quake II RTX v1.8.0 Update

Maintenance update that includes the fixes and features introduced in the past two years.

Highlights:

- Added screen warping when underwater
- Added an option to shoot at the crosshair (aimfix)
- Added new rendering projections: Panini, Stereographic, Equirectangular, Mercator
- Added limited compatibility with Quake 2 Remastered maps
- Merged lots of changes and fixes from Q2PRO
- Fixed various system compatibility and rendering issues

The full Changelog can be found here.