The dragon's harem - Chapter 814 King Of The Void

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.

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.

Nagasawa crossed to Naruto Universe and was bound to Konohagakure.

If Konoha is severely damaged and destroyed, Nagasawa’s lifespan will be reduced.

He panicked at the thought of the upcoming Nine-Tailed Demon Fox’s attack , and the thought of Konoha getting destroyed left him in despair.

Fortunately, while bound to Konoha, he can obtain templates of powerful characters.

At the beginning, He got the Whitebeard template! Since it’s the Whitebeard from the Summit War of Marineford, he can use Tremor-Tremor Fruit’s ability and Haki.

Facing the Tailed Beast Ball, which terrorized Konoha Shinobi, Nagasawa leaped and shattered the Tailed Beast Ball with one punch!

- Description from Novelupdates

One Piece World (Completed): On the eve of the summit, the Navy Headquarters urgently needs a large number of elite combat forces to deal with the Whitebeard Pirates that will attack the Navy Headquarters next.

At this time, Warring States thought of the man who once shined for a while.

“The former admiral, the man with the most potential to become a marshal!”

“He was with Roger, Whitebeard, on this sea.”

“But he was also the only general who made a big mistake and was erased by the navy.”

Recalling the past, Warring States fell into hesitation.

Whether to use him or not, this will make the Navy take great risks.

The World of Naruto (Hot Serial): Starting from becoming the younger brother of Golden Shining, starting from the night of the Nine Tails, subverting Konoha and subverting the ninja world.

Sarutobi Hiruzen: No one would have thought that the young man who had been mediocre for twenty years would possess a terrifying strength no less than that of his elder brother.

No one would have thought that Konoha’s golden flashes were two men!

- Description from novelbuddy