Why did Li Shimin kill Dan Xiong Xin?

Dan Xiong Xin almost killed Li Shimin once. When attacking Luoyang, Dan Xiong Xin took Li Shimin with a gun. If Xu Shiqi hadn't stopped Dan Xiong Xin in time, I'm afraid Li Shimin would have died.

2, Dan capricious, unbearable reuse, shi biao design let Zhai Rang, Dan directly kowtow to shi biao for mercy, don't revenge for Zhai Rang. Later, when Shi Biao was defeated in the battle with the king, Dan took refuge in the king without hesitation.

3. The king played a honey trap on him. When Shi Mi and Wang were at war, he escorted the Shi Mi family to Zheng and coerced them to surrender to the king.

Extended data:

Dan Xiong Xin (? —620), a native of Cao Zhou (now northwest of Cao County, Heze City, Shandong Province). He is good at making Ma Jiao, and the world calls him "Flying General". In the third year of Wude (620), Li Shimin led the army to attack Luo, and Dan led the army to battle.

Dan Xiong Xin pointed a gun at Li Shimin's head, and Xu Shiqi appeared to stop Dan Xiong Xin, so Dan Xiong Xin quit. It is said that Li Shimin was very embarrassed this time, so he hated Dan Xiong Xin.

In May of the same year, Wang was defeated and Dan surrendered. Li Shimin is determined to lay off Dan Xiong Xin. Xu Maogong cut off a piece of his own meat and gave it to Dan Xiong Xin, saying that he had not forgotten his original oath and would take good care of his wife and children. Dan Xiong Xin ate it and died.

References:

Baidu Encyclopedia-Dan Xiong Xin