In " Joy of Life," the masterminds behind the killing of Fan Xian on Niulan Street were Lin Gong, the Eldest Princess, and the Second Prince. Lin Gong was the elder brother of the Eldest Princess. He had worked with Wu Bo 'an to secretly plan the assassination. The Eldest Princess did not want Fan Xian to marry Lin Wan 'er, so she found Lin Gong and used him to kill Fan Xian. The Second Prince also participated.

Who in Northern Qi wanted to kill Fan Xian? The person behind the Northern Qi secret agents who wanted to kill Fan Xian was Lin Gong. Lin Gong was Lin Wan 'er's older brother, and also the Crown Prince and Eldest Princess's man. He had arranged for Cheng Jushu to assassinate Fan Xian on Niulan Street because Fan Xian had come to the capital to snatch the Eldest Princess 'palace treasury and marry Lin Wan' er. This had aroused Lin Gong's anger.
Who in Northern Qi wanted to kill Fan Xian? The person behind the Northern Qi secret agents who wanted to kill Fan Xian was Lin Gong. Lin Gong was Lin Wan 'er's older brother, and also the Crown Prince and Eldest Princess's man. He had arranged for Cheng Jushu to assassinate Fan Xian on Niulan Street because Fan Xian had come to the capital to snatch the Eldest Princess 'palace treasury and marry Lin Wan' er. This had aroused Lin Gong's anger.
There were many reasons why Northern Qi wanted to kill Fan Xian. First of all, Shen Zhong believed Fan Xian was a threat to Northern Qi. He was worried that Fan Xian's existence would bring trouble to Northern Qi, so he planned the assassination. Secondly, Shen Zhong and Shang Shanhu had a grudge. Shang Shanhu's foster father had died in Shen Zhong's pursuit, so Shen Zhong hoped to use Fan Xian's death to satisfy Shang Shanhu's desire for revenge. In addition, the Eldest Princess Li Yunrui had also instructed Northern Qi to send the killer Cheng Jushu to assassinate Fan Xian. Fan Xian had come to Jingdou to rob the Eldest Princess of her palace treasury and marry Lin Wan 'er. This had aroused the Eldest Princess's anger. In short, Northern Qi wanted to kill Fan Xian because they believed Fan Xian was a threat to their interests or to satisfy their personal desire for revenge.
Eldest Princess Li Yunrui had Northern Qi send the killer Cheng Jushu to assassinate Fan Xian.
Who in Northern Qi wanted to kill Fan Xian? The person behind the Northern Qi secret agents who wanted to kill Fan Xian was Lin Gong. Lin Gong was Lin Wan 'er's older brother, and also the Crown Prince and Eldest Princess's man. He had arranged for Cheng Jushu to assassinate Fan Xian on Niulan Street because Fan Xian had come to the capital to snatch the Eldest Princess 'palace treasury and marry Lin Wan' er. This had aroused Lin Gong's anger.
There were two reasons why Fan Xian agreed to go to Northern Qi. First, the Qing Emperor promised Fan Xian that as long as he returned alive, he would immediately arrange his marriage to Wan 'er. Secondly, Fan Xian had agreed to go to Northern Qi to prove his ability. After he had driven the Eldest Princess out of Jingdou, he had left behind a big problem. The Qing Emperor had not only sent Fan Xian to Northern Qi to test him, but also to train him and allow him to grow rapidly. During his time in Northern Qi, Fan Xian had found some secrets regarding the Temple. At the same time, he had learned of his own origins. The relationship between Fan Xian and Wan 'er had gone through some ups and downs, but in the end, they still decided to be together. Before Fan Xian went to Northern Qi, he had promised Wan 'er not to get involved in romantic affairs. However, in Northern Qi, he met Haitang Duoduo and developed feelings for her. Fan Xian's decisions and actions played a key role in the development of the plot. Through his own efforts, he had made a huge contribution to the marriage alliance between Nan Qing and Northern Qi.
It was said that the Eldest Princess had instructed Lin Gong to arrange for the Northern Qi ace Cheng Jushu to assassinate Fan Xian. Lin Gong was Lin Wan 'er's older brother, and also the Crown Prince and Eldest Princess's man. He obtained the token to control Cheng Jushu and smuggled him into the city. Lin Gong had ordered Cheng Jushu to kill Fan Xian because he didn't want Fan Xian to marry his sister, Lin Wan 'er. Thus, it could be said that Lin Gong had ordered the Northern Qi aces to kill Fan Xian.
The Eldest Princess Li Yunrui had ordered the Northern Qi ace Lin Gong to assassinate Fan Xian.
Regarding the question of who had ordered the Northern Qi ace to kill Fan Xian, the following conclusion could be drawn: According to the descriptions in document 1 and document 2, the Northern Qi ace Cheng Jushu was sent to the Qing Kingdom to assassinate Fan Xian by the Northern Qi Eldest Princess and Eldest Princess 'orders. However, document 4 mentioned that the real murderers behind the scenes could be the Second Prince and the Crown Prince. They were fighting for the power of the palace treasury, and Fan Xian had become the biggest chess piece. In addition, document 7 also mentioned that Chen Pingping was related to Fan Xian's assassination. However, she did not want to kill Fan Xian. She only wanted to completely cut ties with him. In summary, although there was no clear answer, it could be speculated that the Northern Qi Great Princess, Eldest Princess, Second Prince, Crown Prince, and Chen Pingping might be related to the Northern Qi aces killing Fan Xian.
Fan Xian's relationship with Northern Qi was based on interests and safety considerations. Fan Xian used his wisdom and caution to deal with the relationship between Qing Kingdom and Northern Qi, displaying superb wisdom and caution. The relationship between Fan Xian and Northern Qi was built on the basis of mutual use and cooperation. Fan Xian and Northern Qi worked together to let his sister Fan Ruoruo become Ku He's disciple and send his brother Fan Sizhe, who had committed a crime, to Northern Qi to take over the palace treasury smuggling. This was also to prevent the Qing Kingdom's hostile forces from attacking him. Fan Xian more or less had Northern Qi's cooperation and assistance in the important matters of the Qing Kingdom.