|Water Margin character|
|Nickname||"Knife Wielding Demon"
|Rank||81st, Ji Star (地嵇星) of the 72 Earthly Fiends|
|Chief butcher of Liangshan|
|Ancestral home / Place of origin||Kaifeng, Henan|
|First appearance||Chapter 17|
Cao Zheng is a fictional character in Water Margin, one of the Four Great Classical Novels of Chinese literature. He ranks 81st of the 108 Liangshan heroes and 45th of the 72 Earthly Fiends. He is nicknamed "Knife Wielding Demon".
Cao Zheng is a butcher from the Song Empire's imperial capital, Dongjing (東京; present-day Kaifeng, Henan). He is nicknamed "Knife Wielding Demon" for his excellent butchery skills. He learnt martial arts from Lin Chong before. He travels to Shandong to start a business but fails and ends up so heavily in debt that he cannot afford the expenses for his journey home. He runs a rented restaurant near Yellow Soil Ridge (黃泥崗; believed to be somewhere in present-day Yuncheng County, Heze, Shandong) to earn some money to pay his debts.
Becoming an outlaw
Yang Zhi is tasked by Grand Secretary Liang Shijie to supervise a group of soldiers escorting a convoy of birthday gifts to Dongjing for Cai Jing, the Imperial Tutor and Liang's father-in-law. When they pass by Yellow Soil Ridge, they are tricked by Chao Gai and his friends into consuming wine spiked with drugs that will make them temporarily unconscious. Chao and his friends escape with the birthday gifts when Yang Zhi and his men are knocked out.
After regaining consciousness, Yang Zhi deserts his men for fear that he will be punished for failing his mission. He wanders around in despair and arrives at Cao Zheng's restaurant. He attempts to leave without paying after having a meal but is stopped by Cao Zheng. A fight breaks out between the two of them. Neither of them is able to overcome his opponent after several rounds of fighting. They are so impressed with each other's skill that they stop fighting and become friends after introducing themselves.
Cao Zheng suggests to Yang Zhi to join a bandit gang based on a nearby mountain, Mount Twin Dragons (二龍山). They travel there and meet Lu Zhishen along the way. Lu Zhishen tells them that Deng Long, the bandit chief, refused to let him join the gang and denied him entry to the stronghold. Cao Zheng devises a plan for the three of them to take over the stronghold.
Lu Zhishen pretends to be drunk and allows Cao Zheng and Yang Zhi to tie him up and bring him to Deng Long. Deng Long is pleased when he sees Lu Zhishen and wants to kill him, but Lu awakes and breaks free. The three of them kill Deng Long, take over the stronghold, and become the new leaders of the gang. Cao Zheng and his companions at Mount Twin Dragons travel to Liangshan Marsh to join the outlaw band later.
Campaigns and death
Cao Zheng becomes the chief butcher of Liangshan after the Grand Assembly of the 108 Stars of Destiny. He is in charge of overseeing the slaughtering of cattle and poultry. He follows the Liangshan heroes on their campaigns against the Liao invaders and rebel forces after they have been granted amnesty by Emperor Huizong. He is killed by a poisoned arrow in the battle of Xuanzhou (宣州; around present-day Xuanzhou District, Xuancheng, Anhui) during the campaign against the rebel leader Fang La.
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- Buck, Pearl. All Men are Brothers. Moyer Bell Ltd, 2006. ISBN 9781559213035.
- Zhang, Lin Ching. Biographies of Characters in Water Margin. Writers Publishing House, 2009. ISBN 978-7506344784.
- Keffer, David. Outlaws of the Marsh.
- Miyamotois, Yoko. Water Margin: Chinese Robin Hood and His Bandits.
- (Japanese) Ichisada, Miyazaki. Suikoden: Kyoko no naka no Shijitsu. Chuo Koronsha, 1993. ISBN 978-4122020559.
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