During the spring time of year thirteen, rain poured down upon a city in the region of the Tang empire.
This city is the city of Wei located in the northwestern borderline of the empire. Since the original purpose of the settlement was to counter the invasion of barbarians from the Great Plain, the walls of the fort have been reinforced to an extreme degree. As a result of the enhancements, the walls protecting the city had a sturdy and muddy external appearance.
When the wind started to blow during the dry seasons, the mud on the walls will break off and swirl around in the air only to land on the cheaply made military camps and on the soldiers themselves. The mud invaded every part of the city painting the city brown from inside out. When people went to sleep and shook their blankets, a mini-sandstorm can form out of the dust.