Many, perhaps most fantasy lands are monarchies, which can be ruled well when the monarch is a clever and able man or woman devoted to his or her people. But what happens when the monarch is ill, or is tyrannically cruel, or a young child, or is otherwise blatantly unfit to rule? How can he or she be dealt with without risking civil war as powerful nobles fight for the crown?
One of the current political paradigms of the Cosmic Era.
The plague of the Petroleum Era, the true bane of organized government
Perhaps those that practice elemental magic begin to take on characteristics associated with their chosen element. For instance, an earth elementalist might be prone to agoraphobia, while air and possibly fire elementalists might have problems with claustrophobia. Water elementalists might always seek the path of least resistance. A fire elementalist might have a cat's opinion of water. This could also apply to physical differences. Fire elementalists might have a freakishly high metabolism and a permanently high body temperature. Water elementalists would probably never get dehydrated, but might slow down a lot when it's cold. Etc, etc.