Reborn with an Old Enemy on the Day of our Marriage - Chapter 38 - The Transformation of Black Sheep

Lingyun, a fierce and savage cultivation genius takes over a dead teenager’s body. Coincidentally, they are both named Lingyun. Set in a alternate version of the 21st century, teenager Lingyun has been killed by someone with a grudge.

An innocent boy from Earth who was sheltered all his life finds himself reincarnated into a world full of magic, a world as beautiful as it is horrifying. Fate brings him together with his new loving mother and sister, and they face the trials together as a family. Follow their incredible story as they struggle to survive and create a better life for themselves.

Her original self was a powerful jiangshi who had cultivated for innumerable years. However, when she attempted to unlawfully enter the world of the immortals, she was discovered by the Jade Emperor and thrown into the mortal world as punishment. Her soul then left her corpse, fusing with the body of the Motian Dynasty’s sixth princess. She didn’t even have a chance to fully comprehend her current circumstances before her maid unexpectedly ignored her mistress, even publicly provoking her!

“What? That weak and cowardly idiot who has neither her father’s love or mother’s favor actually mistook her older sister as her maid?! All the royal princes in the world loathe her?”

“Damn you! This old lady will let all of you understand why the flowers are so red!”

“Hey! Did you hear? That cowardly sixth princess unexpectedly snatched away the man that the eldest princess favored today!”

“How is that interesting news? That fourth princess who ran always ran amuck in the capital city is now confined to her bed now!”

The good-for-nothing counterattacks! The previously cowardly and incompetent sixth princess suddenly reveals her exceptional talents! She is full of radiant elegance, and unparalleled disdain!

She is driven by the desire to shed no more tears! However, if she had known what would happen later, she would have been better off acting stupid! She had calculated thousands, tens of thousands of scenarios, but had never calculated one where one day, her own prey would unexpectedly turn around, and ruthlessly bully her instead! Damn it, she still hasn’t sucked any blood yet!

- Description from Novelupdates

This stands at the forefront of strategy guides to Life (a shitty video game)!