Plague / Epidemic
Year 593: The Year of the Hag. The most virulent disease ever known infects nearly half the souls on the planet, driving those who catch it into a violent fever rage. Cultures and societies fall and the population of Valine is decimated, with more than 1 in every 10 individuals a victim to either the disease or the violence that it causes. The source of the disease is eventually traced to a coven of hags on Atrain that worship Qyrad and aimed to wipe the sentient species from the world entirely. A coalition army of two dozen different species marches to destroy the coven utterly. The site of the resulting battle remains an area of mutation and disease that few dare to tread more than 400 years later.