Briefly describe the story of "Warm wine kills Hua Xiong" in Chapter 5 of Romance of the Three Kingdoms.

Cao Cao recruited soldiers and joined forces with Yuan Shao, Gongsun Zan and Sun Jian to attack Dong Zhuo. Liu Bei, Guan Yu and Zhang Fei went with Gongsun Zan. Hua Xiong, the general of Dong Zhuo, defeated Sun Jian, the pioneer of the Tenth Eighth Route Army, and killed two generals before the battle. He is very proud. The 18 th Route Warlord panicked and was at a loss. Yuan Shao said, "It's a pity that my generals Yan Liang and Wen Chou are not here, otherwise I am not afraid of Hua Xiong." As soon as the voice fell, Guan Yu shouted, "The young man is willing to cut off Hua Xiong's head!" Yuan Shao thought Guan Yu was just an archer on horseback and said angrily, "We have hundreds of generals on the 18th Route, but we want to send an archer on horseback. Doesn't it make Hua Xiong laugh? " Guan Yu said loudly, "If I can't kill Hua Xiong, please cut off my head." Cao Cao listened and appreciated it very much. So he poured a cup of hot wine and handed it to Guan Yu, saying, "General, drink this cup before you kill the enemy." Guan Yu took the glass, put it on the table and said, "Wait until I kill Hua Xiong!" Say that finish, carrying a broadsword on the horse.

Guan Yu was so skilled in martial arts that he soon cut off Hua Xiong's head. Back to the barracks, Cao Cao quickly picked up the glass on the table and handed it to him. At this point, the wine in the cup is not cold. ......