I felt the world needs this information even though its not gaming related (well, it kinda is). If I got another Candy Crush or Farm Heroes invite I was gonna commit mass friend deletion. So now we can all rest easy and just simply block those poor, lost souls.
http://facebook-touches.blogspot.com/2014/02/how-to-block-game-requests-on-facebook.html
http://facebook-touches.blogspot.com/2014/02/how-to-block-game-requests-on-facebook.html