Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Ace of Spades: Battle Builder - Say hello to the creative shooter. Create your battleground, destroy it, then create it again.
Quake - Quake is a series of first-person shooter video games released by id Software.
Lunacraft - Lunacraft focuses on Endless Creativity and Exploration elements.
Counter-Strike - Counter-Strike is a PC-exclusive FPS video game developed by Valve Corporation.
Banished - As always, Email support (at) shiningrocksoftware (dot) com if you have any issues. This will likely be the last update of Banished, except for any major bug fixes. The OSX and Linux versions development has stopped, and won't be released.