I Made a Game Featuring Constellations - Chapter 121

Ron finds himself reborn in the world of One Piece, stranded on a remote island in the East Blue. But he's not just any ordinary child—he’s bonded to a mysterious sign-in system that grants him powers with every new location he visits.At his first sign-in, he unlocks the legendary Sun Breathing Technique, along with a boost to his vitality. From Shitmotsuki Village to Skypiea, Enies Lobby to Marineford, Ron travels the world, collecting extraordinary rewards that make him a force to be reckoned with. The Raikiri, one of the 21 Great Grade Swords, Armament Haki, Observation Haki, and more fall into his hands.As Ron steps onto the battlefield of Marineford during the legendary Summit War, the mightiest warriors—Four Emperors and Marine Admirals alike—pause, stunned by his presence. But Ron merely waves them off, “Don’t mind me. I’m just passing through.”Join Ron on his journey across the Grand Line as he signs in at iconic locations, growing stronger with every step. This is not just an adventure—it’s a legend in the making.

The celestial celestial beings who lived for more than 100,000 years were born and reborn in a small monk in a human world.
His motto: “It’s not as good as a medicinal medicine for ten years of hard work.” “Even if you practice a copper-iron bone, it’s not enough for my soldier’s attack.”

- Description from Novelupdates

Due to the abnormal arrangement of her sixth chromosome, she became a legend in genetic medicine. This is because her vision and hearing are 21 times greater than those of a normal human, while her running, jumping, and arm strength are 33 times stronger, and her regenerative and self-healing abilities are as high as 84 times those of a normal person. However, her father hated her, and people around her disliked her, regarding her as a monster.However, he was the only one who would like to be friends with her. He is the sickly yet most drop-dead gorgeous man in the entire imperial capital. Three steps will make him pant as if he'd just finished a full marathon, and taking five steps was enough to make him cough like a chain-smoker.It is said that one would easily forget the beautiful people of the world upon laying eyes on him.She said, “This pretty boy belongs to me.”

One of the few self-cultivator who exist in this modern world; due to an unfortunate event, completely destroyed his body in an explosion. Using all his effort to save his primordial spirit, he ended up in an strange magical world and had to start all over again. From a fallen aristocrat to the Warlord of Chaos, this can no longer be summarise as legendary; this is the life of the God of War.

- Description from Novelupdates