This is a 3-day trial passes on Steam for the amazing FPS Red Orchestra 2: Heroes of Stalingrad.  They are developed by Tripwire (Killing Floor) and focus on combat realism in WWII Eastern Front.  It is a PC exclusive and generally attracts an older more sophisticated crowd geared to team-play.  If you are sick of all the immaturity on COD: Modern Warfare or BF3 or want to try a different style realistic shooter, you basically have nothing to lose trying out this game with a 3 day trial pass.

https://www.youtube.com/watch?v=D8FR5x9a9mk  << video of gameplay

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