it has to be a game where u can word together to get quests just like in Gunz only now im looking for the same thing but with more quests then stupid gunz :P
and the graphics has to be good no crappy graphics plz :P
You can try Exteel, its sorta quest like, set futuristic with huge mechs, fighting off hordes, google it You can make PVP rooms, Objective rooms and Quest rooms (Well I would classify it as quest) and it is definantly a co op type of game.