Toaru Majutsu no Index - Volume 3, Chapter 3: Railgun. Level5.

In her past life, Michelle was an ordinary doctor who worked in a small hospital, but once in a while, a strange envelope would arrive at her apartment and she would take up a weaon and turn into a deadly assassin known for her stealthiness. But being a top assassin, Michelle had many enemies and ended up dying, only to wake up in the body of Michelle Grace, a pampered young miss in a world similar to ancient dynasties, except that cultivation existed there. Not everyone could cultivate, but Michelle Grace could.The original Michelle Grace was engaged to the Crown Prince, and he killed her before Michelle took over the body, so after making a deal with Michelle Grace's father, the Archduke, Michelle took on the name Grace and started a revenge plan on the Crown Prince, his lover, his mistress and his father, the Emperor.A bit troublesome: Michelle gained the attention of two men who together were the Dark Lord. They were horrifyingly powerful, so Michelle had to be careful around them. Luckily, they didn't have in their plans harming her, as they were intrigued by her constitution. Michelle possessed a rare blood, which they could use.

Shi Jin once read a book. It was supposed to be about satisfying the desire for vengeance.

The main character, also named Shi Jin, was the sixth son of his harem-novel-protagonist-like father. All was well—while his father was alive. But after his death, Shi Jin’s five elder half-brothers tormented him, eventually leading to his death. The protagonist was reborn, determined to take revenge, and… the novel was discontinued.

That day, Shi Jin almost spat blood and dropped the book into a shredder. The next day, he died in a car accident. Somehow, when he came to, he had transmigrated into a teenager, a youth also called Shi Jin.

There was only one problem. His father had just died. His older brothers were about to torment him…

Shi Jin: Let’s eliminate my brothers’ hatred, my goal is to keep my life!

- Description from Novelupdates

“They only call me mad because they're unable to comprehend me.”After recovering from trauma, Dan was just about to reconnect with the world when some cursed force yanked him into another world without warning.He became, Jules Evanava, a similarly traumatized minor character from the novel, Aftermath of Destroyed Worlds.Jules was now the heir to the strongest clan in the world, thanks to their esteemed, world-balance-altering artifact—but there were thorny strings attached.On the same day he arrived, he was thrown into a mission meant to end with his death.Yet he survived, seizing the Archangel of War’s power in a gamble with death—high risk, higher reward.Blood Manipulation, the Crimson Sigil, War Forged—a sentient sword—and Bloodlust Control were just the beginning. There was more to come. So much more.And with each new power and growth, something in him cracked. Sanity frayed, slowly but surely, as Jules danced closer to the edge of madness.Now, with enemies in his own clan and chaos rising across multiple lands—and even space—Jules must navigate a brutal world on the edge of collapse.Armed with the novel's knowledge and his growing abilities, Jules was going to survive it all—even if he had to become the very madness they struggled to understand.

A lifetime ago, Chu Xun was shackled and thrown in jail on false charges. For three whole years, he suffered extraodinary torment from his cellmates every day. Even though he had escaped death many times, he still died from his cellmates’ fists the day before he was to be released.

After death, Chu Xun transmigrated to a different world of cultivation, where cultivation was the one true path. Carrying the weight of his hatred, Chu Xun began to cultivate in hopes of becoming an Immortal Emperor, who could manipulate heaven and earth and travel through time. After painstaking cultivation of three thousand years, he succeeded. Then he sacrificed all his cultivation without hesitation and returned to the day before he was to be released.

This life, he wanted to find out the truth and the one behind his murder in last life. He would continue to cultivate and strengthen himself so that the tragedy would not repeat itself. He wanted to master his own destiny.

In this life, what people would Chu Xun encounter and what experience of love and hate would he have with them? What difficulties would he encounter and how would he overcome? The answer is the book.

- Description from Novelupdates