Casual, the "melee if you can get to it, pistol-sniping if you can't" difficulty? The "Oh, holy crap, I haven't leveled since I became a Spectre, lol whoops, guess I should add some skill points and go fight Saren now" difficulty?
I think it's pretty obvious by this point that the guy either a) is trolling or something or threw his xbox controller/PC out of the window and gave up or c) went back to playing Modern Warfare 2 or something.