Records of the Three Kingdoms
Hua Xiong was a commander under Dong Zhuo. Sun Jian’s biography says that at Yangren Sun Jian fought Dong Zhuo’s army, broke it, and killed its commander Hua Xiong. That is Chen Shou’s text. Hua Xiong has no biography. The killer is not written as Guan Yu. At the time Guan Yu followed Liu Bei, and Liu Bei was in the north under Gongsun Zan, not in Sun Jian’s army.
Romance of the Three Kingdoms
The novel puts Hua Xiong at Sishui Pass. He kills Bao Zhong, Zu Mao, Yu She, and Pan Feng, and Yuan Shao’s officers go pale. Guan Yu takes the order. Cao Cao pours wine. Guan Yu returns with Hua Xiong’s head while the wine is still warm.
This is Guan Yu’s first fame in the book. It replaces Sun Jian’s victory at Yangren. In the novel Sun Jian loses his red scarf and becomes the man Hua Xiong has already beaten.
Reference: Wikipedia · Hua Xiong