Fu Gongyi knew that his biggest obstacle was Wang Xiongdan, he was Du Fuwei's most trusted adopted son and the most favored general, and this person was absolutely loyal to Du Fuwei, which was comparable to his own son, otherwise Du Fuwei would not have handed over the military power of the Jianghuai Army to him.

If Fu Gongyi did not get rid of Wang Xiongdan, the mutiny would not have succeeded.

Therefore, Wang Xiong became the target of Fu Gongyi, and he could be pierced through his heart at any time and fell into the biggest danger in his life.

Fu Gongyi used a poisonous plan - anti-plot, he and Du Fuwei can wear a pair of pants since he was a child, so he naturally knows what his handwriting is like, so he forged Du Fuwei's handwriting and wrote a letter to Wang Xiongdan. The letter reproached Wang Xiong for having two hearts, trusting him in vain, accepting him as his adopted son, and giving him the most important military power.

Wang Xiongdan is a brave and resourceful general on the battlefield, but his brains are not enough in political struggles, and he is not at the same level as the treacherous and cunning Fugong Yi at all, and he can be regarded as a political novice.

After Wang Xiongtan received the letter, he saw that it was the handwriting of his adoptive father Du Fuwei, and did not doubt it at all, but instantly fell into sadness and couldn't extricate himself, thinking that he was loyal to his adoptive father, so he suspected him, which was simply blaspheming his loyalty.

Wang Xiongdan's behavior is in the heart of Fu Gongyi, which simply makes him happy.

Fu Gongqi was serious on the surface, but in his heart he excitedly took over the Jianghuai army, and then forged Du Fuwei's secret order, saying that he was abused by Li Tang in Chang'an, and asked Fu Gongyi to rebel and rescue him from the dire situation.

First of all, Fu Gongyi's imitation of Du Fuwei's handwriting is flawless; Secondly, at that time, there were no telephones, Internet mail, and communication had to rely on horses to travel thousands of miles to deliver letters, and Jianghuai could not ask Du Fuwei about the real situation in time.

Therefore, Fu Gongyi's treacherous plan succeeded properly.

With the appeal of Fu Gongyi in the Jianghuai army, coupled with Du Fuwei's forged secret order, the mutiny was very smooth, it was as easy as the persimmons on the tree ripened and fell to the ground, and the people under the tree picked them up and ate them.

In August of the sixth year of Wude (623), the Jianghuai army announced its independence from Li Tang and regained its independence.

When Wang Xiongtan was living a sullen life at home, Fu Gongyi sent someone to his home to persuade him to submit, and he suddenly realized that he was a fool and was deceived, but the general trend has gone, and he can no longer stop it, so he can only jump with his feet in anger, his lips are black, and he has to vomit blood a few times.

Wang Xiongtan was still loyal to Du Fuwei, and sternly refused Fu Gongyi's persuasion to surrender, and was finally killed by Fu Gongyi.

His old ministry rebelled, and Du Fuwei was so angry that his lungs were about to explode.

The history books do not record whether Li Yuan blamed or punished Du Fuwei for this, but he lived in Chang'an with a sigh of repercussion, and there must have been a sense of trepidation.

In the spring of the seventh year of Wude (624), the Tang army launched a general attack on Fugong with Li Xiaogong, the king of Zhaojun, and Li Jing, Li Shixian, and Kan Ling as generals. At this time, Du Fuwei died violently in Chang'an, and the cause of death is unknown. According to the "New Tang Dynasty Book", Du Fuwei was a good elixir, and died of mica poisoning by mistake. Poisoning is real, and how to poison can make people think infinitely.

Among them, Kan Ling is also Du Fuwei's adopted son, and Wang Xiong is called a double hero, when Du Fuwei entered the Tang Dynasty, he brought him to Chang'an.