MTL - My Wife Is the Martial Alliance Head - ~ Postscript 006 Survival of the fittest

Leon is an average high school student who likes to watch anime and read novels.
He's about to cross the street, only to be greeted by a truck and died.
But, he got reincarnated as Uchiha yet dead again because Itachi killed him.
Leon got reincarnated again as the grandson of the recovery girl.
He got kidnaped and tortured by All For One.
After his third death, he got reincarnated as a son of Bibi Dong.
In this fourth life, he wants to change his fate to become the strongest.

Note: Please read the tag before reading.
- English is not my first language, so there would be grammatical mistakes in this story.
- Please give my story a proper review.
- I accept a suggestion, but no spam!

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.

Jiang Yu was a small mermaid who couldn’t sing. He had always felt inferior because of this. Not until he came to shore to find the father of his baby did he discovered that his talent turned out to be acting. Since then, he had trampled on the scum man, going on the acting road all the way, and progressing triumphantly.

Qin Shen: ??? You ran away after sleeping with me, and you still call me a scum man?

The not yet met Jiang Yu: Oh, it’s a small star who wants to hug my thighs.

The after contact Jiang Yu: Really fragrant.

Qin Shen found that things around him often disappeared, at first it was handkerchiefs, then ties, and then his shirt. And every time he lost something, there will be more pearls around him. One day, he caught all the things he had lost in that room, and he saw a little thief in his pajamas.

The little thief Jiang Yu is not happy, pointing at the jar of pearls, I am not a thief, I have money for you.

- Description from Novelupdates

What is an immortal? They are mortals who have transformed themselves by taking the essence of heaven and earth, shedding their mundane bodies, and gaining the creation of the universe.This is a legend of a lowly beast s*ave who is discontent with his fate and fights against all realms.He knows that only by becoming an immortal can this realm finally catch a breath.