20. RELIGION
Religion has been the cause of more strife, armed conflict and discussion than pretty much anything else man has made. As all religion attempts to answer the big question that faces everyone (i.e. 'What's next?') it apples to everyone. Hence, because we are by nature a violent race, it becomes perfectly acceptable to bash in someone else's head with a rock screaming 'God is love'. You can't not have stuff like that in games. It gives strife and consequences. Consequences like being boiled in oil, for example. Nations will go to war over the arrangement of words in a book or a rather sloppy editing job by some 50 year old virgin. You can't beat that for the sheer drama.