There were only three Legendary ranks since time immemorial and why there were only three and why two didn't exist, nobody knew.
There are many Supreme ranks in hiding or in other dimensions and only fifteen roam around the world. Nobody really knows who is where or who is a Supreme rank and nor do they care.
Once in a while, certain beings from the other dimensions come out into the main world to cause chaos. They were either the ones who just found out about dimension gaps and thought of taking control of the other side or the ones who were previously into hiding to improve their strength.
Time to time, these beings would come out and try to create mass genocide or destruction of property. To stop them, guilds give certain mandatory missions to their members and those who complete it, get incentives or class upgrades. They might even get rewards and medallions from certain countries in which such a disaster had been stopped.
