The Kura Sau -also referred to as the Gou Zhang- are a society of those Hsien that surrendered themselves to the Yama Kings and are regarded as a part of the Mu Courts. As a result, they are able to travel to Yomi Wan without suffering the curse of the August Personage In Jade. In addition, they have their own branch of Wu Tan known as Hac Tao, a vile art that allows them to carry the tainted chi of the Thousand Hells into the world.
They strive to fulfill the agendas of their dark masters, bringing on the Sixth Age and corrupting most of the Middle Kingdom. Most are dark reflections of the original Hsien and some answer even prayers, on condition that they involve bloodshed and satisfaction of darker urges. Some claim that the Kura Sau are even responsible for the corruption of some dragons and phoenixes, tempting them with promises of power that only the Yama Kings can grant.