Edron Demon Wars

Since eternity and for reasons long forgotten two demon races wage war against each other near to the entrance of the demon forge. Neither of them could clam dominance over the other and only the deeds of mortals may change the tide of battle. Since the demons are quite similar in power they will eternal fight in a status quo. When one side is severely weakened by outsiders the other will finally gain the upper hand and their leaders, smelling victory will come out of hiding. The slaying of the leaders will reset the status quo though.