Gray Cloud Valley.
This was a desolate area in the southern domain of the Great Yan Nation, said to be inhabited by a fiercely temperamental emperor-tier mythical beast. This beast was immensely powerful, and entering its territory could prove fatal.
Strangely, however, neither the high-ranking Beast Tamers from the southern domain nor martial arts masters seemed interested in exterminating this emperor-tier beast that claimed the valley as its kingdom. They chose to turn a blind eye to its presence.
Left with no other choice, the people living nearby could only continually warn passing travelers not to stray into the area, lest they become an added meal for that emperor-tier beast.
Over time, Gray Cloud Valley became increasingly desolate, visited by fewer and fewer people.