Action games
If you don't play games that much, there is a big chance you have played an action game, e.g. a shooter, at some point. This category is full of games that won't let you get bored.
Space Shooter Saga
Rat Invasion
Astro Avenger
Dark
APB Reloaded
Alien Shooter - Revisited
Urban Terror
Luxor 4 Quest For The Afterlife
World of Warplanes
OPERATION7
Knytt
Metro 2033
Prince of Persia - The Two Thrones
Blackshot
UFO Killer
BioShock
RIP3
Enemy Territory: QUAKE Wars
Istrolid
Pirate101
SubRosa
Smokin' Guns
OpenSpades
ACE of SPADES
Skies of War
Crazy Taxi
Shotgun Vendetta
Serious Space Invaders
F.E.A.R.
Discover FDM
Add-on support
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