The classes set it apart from L4D more than anything else. I'd say Cord's mate the Witch Hunter is least clear but the class roles are fairly clear. I'd also say on normal difficulty we weren't using that clearly enough. On higher difficulties it will require different sorts of teamwork to Left 4 Dead.

Me and Cord also played some Civ 5. Or as our save shall be called: Marauding Barbarian Hordes - The Game.