Kuzushi no Oni

From L5r: Legend of the Five Rings

In 1123 when a solar eclipse released the Kuzushi no Oni from its prison in the Spirit Realms after two hundred years of imprisonment it found itself bound to a forgotten estate deep within the Phoenix woodlands. The oni used its powers to unleash a lethal plague spread with magic, known as the Darkfever Plague, and many lives are lost until a group of clever Magistrates locate and destroy the oni. (3E p. 17)

This Shadowlands related article is a stub. That means that it has been started, but is incomplete. You can help by adding to the information here.