a major character in the latter half of the book Shuo Tang, as well as in the sequel. He had a dark skin, and used a Bian (a columnar- and pagoda-shaped traditional Chinese weapon) as his weapon. His teacher told him that he could not survive without his Bian. He started as a blacksmith living in Taiyuan. After Li Yuan claimed Taiyuan's independence from Sui Dynasty, two of Li Yuan's sons, Li Jiancheng (李建成) and Li Yuanji (李元吉) were ordered to recruit soldiers in Taiyuan. However, due to their poor reputation, they could not recruit enough soldiers. Then, Li Yuanji advised Li Jiancheng to recruit under Li Shimin’s name because Li Shimin's reputation was much better than theirs. Thought Li Shimin was the general recruiting in Taiyuan, Yuchi Gong went there and became a soldier. However, he was unfairly treated by Li Yuanji's men. He got angry and left the camp. He thought it was Li Shimin who treated him like that. Later, he joined another warlord, Liu Wuzhou (刘武周), near Taiyuan. The major military officer under Liu Wuzhou, Song Jingang (宋金刚), noticed Yuchi Gong's talent. Song asked Yuchi Gong to be his assistant officer. When Liu Wuzhou and Li Yuan came into a war, Yuchi Gong was extremely active during battles to revenge for the indignity he suffered in Li's camp. He led his men occupied Li Yuan's three cities during one day and eight villages during the following night. Li Yuanji and Li Jiancheng were defeated. At that time, Li Yuanba was already dead, so Li Yuan had to send Li Shimin to stop Yuchi Gong. One evening, when Li Shimin and Cheng Yaojin (程咬金, or Cheng Zhijie 程知节, another warrior known for his three fighting tactics with an axe) were marching, they were ambushed by Yuchi Gong at a creek called Meiliang-Chuan (美良川). Although Li Shimin and Cheng Yaojin were both great warriors, they were defeated. Li Shimin asked Cheng Yaojin to retreat first and find Qin Shubao for help. Cheng Yaojin worried that Yuchi Gong might kill Li Shimin when he was away. Yuchi Gong told him that he would not even try to kill Li Shimin before Qin Shubao was there, or he would die under the Zhijin Gate, a major gate in Chang'an. When Cheng Yaojin left, Li Shimin asked Yuchi Gong why he did not join Li's troop as he was from Taiyuan.