Sauerbraten or Cube 2 Sauerbraten is a free and open source first person shooter game for Windows, Linux and macOS. It comes with multiplayer & singleplayer game play. This is the successor of the old Cube FPS game. It is released under ZLIB license. It also comes with build-in map editor. This comes with some high quality graphics but you can play little older systems without any problem.
Install Sauerbraten on Ubuntu Linux
Cube 2 Sauerbraten is available as a flatpak package from flathub. First you need to install flatpak and flathub on your system and restart it.
Open terminal application and run Sauerbraten flatpak installation command. It will install the latest Sauerbraten First Person Shooter Game on your system.
flatpak install flathub org.sauerbraten.Sauerbraten
You can run this game using this command.
flatpak run org.sauerbraten.Sauerbraten
And uninstall Sauerbraten using below command.
sudo flatpak uninstall org.sauerbraten.Sauerbraten