MTL - Konoha: Make Uchiha Great Again - Chapter 306 awakened shadow

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

He lived from BC to the Middle Ages, from the Renaissance to the Industrial Revolution, and from Cyberpunk to the Interstellar Age. He has been a king and a prophet, a knight and a nobleman, a versatile artist, a genius inventor…
This is a four-thousand-year human epic——
“To us four thousand years from now:
“Is the world at peace? Is famine extinct? Can people touch the stars? How long is the human lifespan? How far is the boundary of the earth? Human…do you remember us?”
——Excavated from Earth Age Tenth Century BC, Solomon Prayer Book.

- Description from novelbuddy

Dragon 5th is a powerful lord with incredible martial arts, and yet is wasting away from a fatal disease. The only medicine which can cure his sickness lies in the clutches of his venemous ex-wife, Madam Lovesickness, and is guarded by 7 dangerous killers, fugitives of the martial world. To retrieve the antidote, Dragon 5th hires Liu Changjie, a skilled martial artist who loves drinking and women, but has a mysterious past. All is not what it seems in this wuxia heist story.