Chang Sumian went down the mountain to avenge his senior sister, and never went back. Bai Yuelou has been on Yaoquan Mountain for forty-nine years, from having nothing to having a first apprentice and a second apprentice, and then losing the first apprentice and the second apprentice. He went down the mountain to look for it, but met the third apprentice on the way.
Concept: human nature, good and evil, destiny