FPS (first person shooters)
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The game, that started as Quake mod, is no longer a mod. It's a stand alone game. This means that you can download and install the game, without installing the Quake first (or at all)
The game is multiplayer, but it has a singleplayer option, fighting bots.
Official site:
www.smokin-guns.org
www.smokin-guns.org
Game trailer: