Huang Xin used to be an imperial general from Qingzhou. He is famous for his prowess in martial arts. Once, he boasts that he can eliminate the outlaws on three mountains. He is thus nicknamed "Guardian of Three Mountains". Huang Xin is one of the scouting generals of the Liangshan cavalry. After the victory over Fang La, the emperor reinstates him as a general in Qingzhou in recognition of his contributions.