Echoes of Heaven
The Age of Chaos
Even those barely remembering anything from their school years can tell you that this was an age of war. At one point or another every mortal race warred on the others and just as often amongst themselves. However, it is also known that during this age great evils came into existence. This was the age when mortals discovered that those who represented great enough evil would be tainted by Bamon and become demons or even archdemons upon their violent deaths. It was also during this age when undead first began appearing.
Of course those who were paying attention in school would argue that these evils appeared even sooner.