In the ancient novel Su Xi, the female protagonist, Yun Xi, died while completing a mission. She was the best after 10 years of training, and now there were only four people left.

Answer 1

I don't know if it'll meet your needs, but I'll try my best to recommend a novel that's most relevant to your description." After I Transmigrated, I Spoiled the Big Boss Villain " is an ancient romance novel written by the author, Xing Xing Xiaowen. The general plot of this novel is:

Su Yunnian, the 22nd-century ace female agent, accidentally transmigrated into a book and became the wife of the prime minister, Lin Jian, who was the biggest villain in the book. Even her three children became villains in the future. In order to save her life, Su Yunnian chose to curry favor with her and promised to divorce her after she cured his eyes. However, as they got to know each other, Lin Jian realized that the vicious woman in front of her seemed to have changed into a different person. The three children gradually fell in love with Su Yunnian. With her own abilities, Su Yunnian had made a name for herself in this world. As Lin Jian and Su Yunnian spent each day together, the feelings in her heart gradually fermented. The relationship between the two of them was also a little subtle. It was only when Lin Jian's identity was gradually revealed that Su Yunnian realized that he had an even bigger secret…
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" The Black-bellied Prince's Genius Crazy Concubine " was an ancient romance novel written by the author, Wang Yutong. The general plot of this novel was:

Su Xin, in the 21st century, she was terrifying. As a top-ranked assassin, she died because she was betrayed by someone she trusted and transmigrated to Liyun Country.
Su Xin, the Fifth Young Miss of the Su Family of the General's Estate of the Li Yun Nation, was framed and turned into a fool. Her father did not love her, her aunt did not love her, and the only brother who was good to her ran away from home because of her mother's death. Her whereabouts were unknown.
Mu Yechen, His Royal Highness King Jin of Liyun Nation, possessed a supreme status. In front of others, he was cold, evil, domineering, murderous, and mysterious. However, behind the scenes, he was like a obedient little wife. Was this still him…
When the 21st century gold medal killer Su Xin transmigrated into the silly fifth daughter of the Su family, Su Xin, everything would change…
When she found out that she had a biological brother, she searched aimlessly in the vast world. When she needed someone to accompany her the most, he gave her unprecedented warmth.
The boundless world had allowed him to meet her. Perhaps it was fate that allowed him to transmigrate and be reborn.
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" The Little Blessing Wife of a Powerful Official " was an ancient romance novel written by the author Yun Piangao. The general plot of this novel was:

In a novel that she had read before, Su Qingning was willful and vicious, and she tortured the male protagonist badly. In the end, the male protagonist turned around and became a powerful minister of Liang Dynasty. One could imagine what happened to her. Luckily, when she woke up, the abuse she had been going through with the male lead had just begun. Facing the cold and distant male lead, Su Qingning lowered her head. Was there still time to change everything? The plot is fictional, please do not imitate it.
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'Records of the Clouds' was an ancient romance novel written by the author, Ban Liusu. The general plot of the novel was:

The scheming royal princess, whose country was destroyed and family perished, opened her eyes and became the daughter of the person who forced her to death. She planned to return to Li Jing and get closer and closer to the famous King Duan. She was injured and had a dream of her past life. She noticed some clues that she had never noticed before. It turned out that her death in the past was just a conspiracy. It turned out that her past 25 years had been a joke…
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The book," Time Travel: To Be a Rich Man, Not a Wife " was an ancient romance novel written by the author, Chuxin Moshi. The general plot of this novel was:

Su Luoli had accidentally transmigrated to ancient times and became her cousin-in-law, Shangguan Yunhe's stepwife. Initially, Su Luoli thought that Shangguan Yunhe was 'dead', and that she only needed to take care of her mute stepdaughter and live a life of waiting for death. She didn't expect Shangguan Yunhe to come back alive and even get promoted…
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" Time Travel: The Princess's Power Is Dominating the World " was an ancient romance novel written by the author, Little Grassroot. The general plot of this novel was:

A blissful family, because of an accident, her father's departure, and the sisters 'deep friendship, but it was all a dream. After transmigrating, she would face the calamity of the twelve Jade Ladies. It would be an intense struggle, a thrilling journey. How would the female lead, Su Mumu, escape from the sea of suffering and free herself from the fate of the Jade Ladies?
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" The Tragic Struggle of the Quick-Piercing Cannon Fodder " was a sci-fi space-time travel novel written by the author, Sheng He Liu Quan. The general plot of this novel was:

In her previous life, Yun Chuyao died unjustly and ended up in another space after she died. From then on, the high-end plot of allowing her to travel through the three thousand worlds began.
The sulky junior brother who had been bullied, the beautiful and loyal Blood Clan Duke, the peerless nine-thousand-year-old jade-faced Marshal, the iron-faced and gentle Dragon Demon King, the sickly and bloodthirsty black-bellied researcher, the cold CEO who did not mean what he said, and the son of God who cared about the common people…all of them had fallen under her feet!
Yun Chuyao: 'Capture the strategy to overthrow the Prince Charming! It's a one-stop service! Aren't you going to give me a five-star review?'
[Su Shuang, 1v1]
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" The Female Guard " was an ancient romance novel written by the author Qiao Su. The general plot of the novel was:

She was originally the daughter of an official's family, but because her family was raided, she became a guard of the Order Receiving Department by chance. In the days when she was a guard, she could deceive the Minister of Judicial Review, teach the Fifth Princess martial arts, and avoid the pursuit of the Seventh Prince, but would she let go of the old matters from many years ago? What would the sudden appearance of her eldest sister bring her?
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" Poison Pet Agent Ugly Concubine " was an ancient romance novel written by the author, Yun Qingran. The general plot of this novel was:

The stunning female agent traveled through the world, but unexpectedly, she was plagued by a strange illness and fell into layers of conspiracy. She was calm, intelligent, and decisive. She exposed the conspiracy and became famous.
She did not expect to meet a black-bellied man. The world was mesmerized by his gentle and refined appearance. In order not to be controlled by his marriage, she disfigured herself and ran away from the marriage. However, she did not know that she had long been covered by his invisible net. After turning around, she saw a certain someone smiling elegantly." I told you, you can't escape."
Was her transmigration a coincidence, or was it the reincarnation of fate?
"If fate is decided by the heavens, then this king will break the heavens."
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" The Crown Prince's Walk Slowly: The Woman General's Allure " was an ancient romance novel written by the author, Eryue Weiqing. The general plot of this novel was:

As the most outstanding special forces soldier, he was betrayed and died in the snowy night. Her parents had died young and she had gone through great changes. She was cold and indifferent, as if death was nothing. Who knew that one day, he transmigrated and attached himself to the eleven-year-old Su Liuxi, the daughter of the Great General of the West of Daqing Town, Su Xun. His mother secretly harmed him, and his sister deceived him. His life was like a slave. If he wanted to live a peaceful life, it seemed that he could only leave to avoid future troubles. Who knew that he would accidentally enter the military camp, and who would notice him? As the Empire's most noble and elegant War God, he was respected and looked down upon by others. He had been fighting in the royal court since he was young, and he had been fighting for his life. He was decisive in killing, and it seemed that he did not care about anything. Who knew that a small soldier would appear in the army. His strategy was outstanding and he was simply an opponent. She wanted to train and promote him, but who knew that in the end, she would also be involved, and he was still willing to endure it…