The characters get smarter and more sofisticated and it turns into the modern world. Everyone just goes to and from work in a never ending cycle, a select few, elected by the others rule the others in the democratic government they make, and the ones who voted just sit back and complain about it. There is no violence, magic is only used in the work place, and they form different religions based on the race you choose. The Races start to live in different areas and hate the other races. Each race starts wars with the others while preaching racial and religious tolerence. They create a WoW United Nations to try to solve the international problems but, they end up only pointing out the bad guys. Eventually, they create nuclear weapons and destroy each other.
And that is the end of WoW.
Don't worry though, WoW is only in the middle age era. It will take hundreds of years till they start this. Once we start to see the WoW industrial revolution we need to take action.