i use Scientificlinux 6.4 and OpenSUSE 12.3
but i DO NOT use SL6.4 as my everyday desktop OS
For that i run OpenSUSE 12.3
Alien Arena 7.65 IS in the suse OBS repos ,and once obs is installed installing AA is as easy as.
Code:
su -
zypper in alienarena
as for games in CentOS 6.4
there are some in the centos repo
some in rpmforge
a few in elrepo
I know that "word war VI" runs on 6.4
http://wordwarvi.sourceforge.net/
and so dose "Chromium BSU"( NOT googles browser)
http://chromium-bsu.sourceforge.net/
it is possible ( read rather HARD) to build Parallelrealities "virus-killer"( yes it is an EARLY 2000's game )
Most of googles chrome browser games should play