Naruto System in One Piece - Chapter 497: Spear and Shield

After dying from betrayal, Thomas reincarnates as Jolthar Kaelzhar, the neglected son of a powerful clan, just after his brothers kill him. With Jolthar's memories and the blessing of Qalena, Thomas vows to rise from his lowly position and claim power in his new life.

Hundreds of years ago, Human, Celestial Clan and Demon Clan lived together on the Origin Continent. However, a great war broke out between the three races. Shan He, the leader of Human, had discovered a catalogue of methods to forge Divine Weapons. With this catalogue, Shan He led Human to defeat the other two clans and expelled them from the Origin Continent.

The peace did not last long. After the passing of Shan He, the once Glory Empire collapsed. Various forces of Human fell into a long period of wild war for the Divine Weapon Catalogue, but the catalogue was lost during the war.

The Demon Clan took advantage of the internal strife of Human. Under the lead of their new lord, Fen Tian, the Demon army invaded the Origin Continent violently.

Human soon lost a large portion of their territory. At that moment, a mysterious hero suddenly appeared on the battlefield. With a legendary Divine Weapon in hand, he severely injured Fen Tian and forced him to retreat. The united Human army chased the Demon army across the strait and to the Two Realm Plain on the Tranquil Continent.

Once again, the various forces of Human started wildly searching for the Divine Weapon Catalogue…

- Description from Novelupdates

Amidst a disaster, an orphan contracts a sickness.

This is a world filled with despair, teeming with hordes of corpses, mutated creatures, poisonous plants, demons, and gods.The human societal system has completely transformed, with no justice, no righteousness, only might and slaughter.The strong can oppress the weak at will, human order has utterly collapsed, and the law of the jungle reigns supreme. In this world, weakness is the original sin!Some lucky humans have awakened extraordinary abilities, becoming Evolvers, and have risen to the top, possessing wealth, resources, beautiful women, and status.Qin Jun crosses into this doomsday world, awakening the Great Villain System at the start. As long as you are villainous enough, SSS-level talents, gene serums, and potential points are all within reach.Perhaps in the doomsday world, only villains can climb step by step to the peak…