Variations: Xi-Rhinoceros; Xiqu (potentially); Si, Si-Rhinoceros (potentially)
Among the wildlife to be found on Cauldron Mountain, Mount Min and Pray-and-Pass Mountain is the Xi. It is like a black water buffalo with a pig’s head, a large belly, and three-toed elephant’s feet on short legs. It has three horns, found on its nose, forehead, and crown. The nose horn does not fall off and helps it eat. Xi feed primarily on brambles, and therefore often drool blood. It may be the same animal as the Xiqu, which is a man-eating blue-black ox that makes sounds like a baby.
The Si is similar, but blue or green with a single horn weighing 1,333 pounds. Its thick skin could be used as armor.
Guo Pu mocked the Xi for its big nose, and the Si for its tough hide which ironically made it more desirable and vulnerable to human exploitation.
Both Xi and Si have been used interchangeably to refer to a number of large herbivores including oxen, yaks, and buffalo, but they are generally believed to be rhinos.
References
Strassberg, R. E. (2002) A Chinese Bestiary: Strange Creatures from the Guideways Through Mountains and Seas. University of California Press.
