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By May 1, any customer that has ever redeemed a code for our Never Settle Reloaded promotion is going to receive a FREE GAME KEY for Far Cry 3 Blood Dragon by email. Or, if you have a Never Settle Reloaded postcard with a code you’ve not yet redeemed, Far Cry 3 Blood Dragon will be added to the games on the postcard when you finally register the code.
http://blogs.amd.com/play/2013/04/11/fc3bd-nsr/
Far Cry 3 is a stand alone game and doesn't require Far Cry 3 to be played.
I haven't play it yet, but is looks incredibly!