As Li Zicheng's strategist, why didn't the Qing army kill Song Xiance after he was arrested?

Mention Li Zicheng, everyone should be familiar with it. Li Zicheng, also known as King Chuang, was born as a farmer. At the end of the Ming Dynasty, he led the peasant uprising to form an uprising army, eventually overthrew Daming Mountain and established his own political power, so he was once brilliant in history. The Li Zicheng Uprising was really successful, with outstanding talents. In addition to strength, there is a lot of luck. During this period, Li Zicheng also had his own strategist named Song Xiance. After Li Zicheng was killed, Song Xiance survived because he had escaped.

Song Xiance is Li Zicheng's strategist. As the name implies, he has a lot of strategies, so he helped a lot when Li Zicheng attacked Lin Chao and gave a lot of advice. In the Li Zicheng Uprising, Song Xiance invented the circuitous strategy, because the equipment of the insurgents was definitely not as good as that of officers and men, so we had to use flexible tactics to attack the enemy, so we also won.

Song Xiance also asked Li Zicheng to set up a Boy Scout, who took advantage of his body and climbed the city wall with a short knife. The speed was very fast and flexible, which made Daming's officers and men frightened. Besides, Song Xiance knows people's psychology very well. In order to help Li Zicheng establish his prestige, he also shouted many slogans and made up many folk stories to shape the image of Li Zicheng. So these measures are also very effective, and Li Zicheng will soon win the hearts of the people. But Li Zicheng became arrogant after gaining power. He often drank and had fun in the palace, and the atmosphere was very bad. He was quickly defeated by the Qing army.

Li Zicheng was killed by a group of farmers when he fled hastily, while Song Xiance lied that he was just a fortune teller, so he got a chance to live. Since then, Song Xiance has remained anonymous. He also lived by fortune telling in the crowd, so he saved his life by fortune telling and was not caught by the Qing army.