What these guys did was basically get all the games that are in AUR and are not in the repository community, compile them and make available in a repository, saving us from having to compile and keep looking for updates on AUR.
To add the repository + mirrors put this on /etc/pacman.conf:
[arch-games] Include = /etc/pacman.d/archgames_mirrorlist
Create /etc/pacman.d/archgames_mirrorlist and put this:
Server = http://arch.twilightlair.net/games/$ARCH Server = http://pseudoform.org/arch-games/games/$ARCH Server = http://repo.exigen.org/arch/games/$ARCH
Where $ARCH is i686 or x86_64(run arch)
The first is the main repository, the other 2 are the active mirrors until today’s date.
See the site ;)
If you search for games to Ubuntu/Kubuntu see in UbuntuGames.org.