The Ultimate War Of The Apocalypse - Chapter 19 - 18 Costly

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Chuang Shi Shen created a system world in Boredom, where thousands of NPCs travel in various time and space to help the host fulfill his wish. Bei Qiu is one of the NPCs, an NPC whose teeth are stuck in cold water. She protested that NPCs also need to have love, affection, meme, and papapa! Someone directly threw her into the female supporting role strategy system! One of the most difficult and cheating system! Bei Qiu said: “Leader, I am with you, can you hold your hand high?” Zhong Yexuan said: Get out. Raiders president, Raiders monk, why did she become the zombie king? Do you want to attack the orcs who can solve their animal desires anywhere? She said no!

- Description from novelbuddy

[Shelter System successfully bound to host!][Option One: City of Light, save the survivors in the apocalypse and become a glorious and benevolent savior.][Option Two: City of Darkness, humans who enter the City of Darkness can only become your slaves. And you, will be the devil ruling over the apocalypse.]Sorry, I am no saint, I choose City of Darkness! From today onwards, I will be a villain!

[I have led a cautious life, but the system keeps trying to do me in] “Ding Dong!” “Welcome to the Smart Cultivation System!”

“You have chosen to cultivate the Bone Forging Art. The system will start cultivating for you. The system has detected that the host is missing the Bone Tempering Pill. Please wait a moment…” “Ding Dong!”

“The system successfully stole ten Bone Tempering Pills for you, and the cultivation will continue…” “Important reminder, while the system is cultivating, you will lose lose control of the body…”

After getting the Smart Cultivation System, Pei Ling began to grow stronger rapidly. He was prepared to become a deity until one day… “Ding Dong!”

“You have chosen to cultivate an unknown technique. The system has identified this as a dual cultivation method. The system will start to cultivate for you. The system has detected that the host is missing a Dao Partner. The system is looking for a Dao Partner for you…” So, Pei Ling watched as he ran to the fairy’s training room next door, drugged her, and carried her into his room…