Ankoku Kishi Monogatari ~Yuusha wo Taosu Tameni Maou ni Shoukansaremashita~ - Chapter 137.2: The Great Sage

Jun Xie was the number one assassin in modern earth. His skills and knowledge in the field of assassination were unparalleled, his accomplishments unprecedented, his reputation terrified the entire underworld. However, during a mission to retrieve a mystical treasure, a mishap occurred…

He is now Jun Moxie, a sixteen year old super level debauchee, sole heir to the declining Jun family. A family of valiant heroes, left with an old grandpa, a crippled uncle and a debauchee as the sole heir! Accepting the world’s criticism and cold stares with a smile, his new journey begins! His life will be carved by his own will! Rise to the top! Evil Monarch Jun Xie!

“This cup I toast to those I’ve killed in my past life. Forgive me, for there is no chance for you to have revenge. Gulp!

This cup I toast to those whose life I will take in my new life. Forgive me, for you are fated to die by my hands. Cheers!”

- Description from novelupdates

A con-man and policewoman that are legends of their respective professions suddenly die, then are reincarnated and return to the Tang Dynasty of ancient China as little kids.

Accepting their second chance and forced restart, they choose to use the modern knowledge and specific talents that they have in their previous lives in order to live comfortably in this new life.

- Description from Novelupdates

Accused by his enemies, Tang Yin was led to a dead end and died at the hands of his enemies. Even so, fate gave him a new chance, and his soul traveled to a lower world, where he managed to reincarnate.His new body had no cultivation and no family either, so he was now a total cripple in an unknown world, with enemies lurking at his door.Yet, he is the proud Divine Heir, dubbed the 'Divine Son' of the Upper Realm. How could something so simple stop him?That is why he will forge his own path and rise again, this time by the hand of a mysterious power that belongs exclusively to him.'Even if I don't understand why I was chosen as Divine Heir, I will create my own path and forge my own power.' He thought.At the same time, a strange and mysterious system with an attractive power, which it said could help him complete his revenge, appeared before him.[You must become the Host of the Domination System][Do you accept?]

Uchiha Yu traveled through and came to the crisis-ridden Naruto world.

Looking at the scarlet writing wheel in the mirror, Uchiha Yu nodded with satisfaction: “Well, everything is going well so far… smooth hammer!”

Looking at the calendar on the wall, Uchiha Yu felt the malice from this world…

In order to save his life on the night of the genocide, and even take food from the tiger’s mouth, Uchiha Yu decided to train Pokémon hard from today!

Uchiha Yume, use illusion!

A trainer: “Referee, Yu’s dream demon is illegal, it uses illusions!”

Uchiha Yu: “Humph, you absolutely cannot escape this technique!”

Deidara: “Explosions are art!”

Uchiha: “My Pangyan monster’s art is better than yours!”

- Description from novelbuddy