Hei Manlong is the young nephew of the Yunnan ruler Li Shufu in The Story of Yue Fei. He first rides with forces nominally helping Jin because the Song court has neglected his uncle’s title, but his real measure comes when he challenges Yue Yun. Both youths fight with paired hammers. Their blows continue for more than one hundred bouts without a decision, and Yue Yun concludes that he has met a true equal rather than an ordinary frontier officer.
Instead of forcing the contest to a death, Yue Yun draws him aside and explains the disorder facing the Song. Hei Manlong admits that Jin has treated his people poorly and accepts Yue Yun’s offer of brotherhood, taking the younger place in the oath. The scene gives him unusually high standing: the novel uses a long, even hammer duel with Yue Fei’s celebrated son as direct evidence of his power, then turns that rivalry into personal loyalty between the two houses.
Years later Hei Manlong learns that Yue Fei and Yue Yun have been murdered. Furious that distance prevented him from helping his sworn brother, he secretly raises three thousand troops, breaks through three passes, and marches toward Lin’an demanding the guilty ministers. The court cannot easily stop him. What ends the expedition is a letter from Yue Fei’s widow, who warns that private war would stain the loyal reputation he means to avenge. Hei Manlong weeps, sacrifices at Yue Fei’s tomb, and withdraws to Yunnan. His final choice proves that his ferocity is governed by the very loyalty that inspired the invasion.
