Rebirth in One Piece as Deputy Captain - Chapter 23

While the blue light blossoms, the insignificant struggle at the bottom. He grasps the opportunity to change his fate and embarks on an unprecedented path…

Felix Ariel, a typical Floridian, found himself transported to a mysterious kingdom in another world. However, a misunderstanding led to Felix accidentally killing the king, resulting in his untimely demise.Following this tragic event, Felix's spirit encountered a mysterious being who identified as Felix's ancestor. This entity claimed that Felix had been cursed by an unknown individual. For Felix's safety, the ancestor bestowed upon him a system for self-defense.Upon returning to Earth, Felix realized that he would be transmigrated to the alternate world at noon due to the lingering curse. To prepare for this unexpected transmigration, Felix relied on the system, which required him to gather oil and gold to enhance his abilities.Thus began Felix's quest in the other world. With his system, he brought firearms and an ambition to spread liberty... for prosperity and freedom.

Just like how everyone adored heroes in their childhood, a certain young man adored those powers hidden in shadows. After hiding his strength and living the mediocre life of a mob character by day while undergoing frenzied training by night, he finally reincarnates into a different world and gains ultimate power. The young man who is only playing at being a power in the shadows, his misunderstanding subordinates, and a giant organization in the shadows that gets trampled…. This is the story of a young boy who had adored powers in shadows possibly eventually reigning over the world of shadows in another world.

The course of commitments never did run smooth.

After dying on Earth, the King of Mercenaries is reborn as Su Mo in the Firmament and Continent. In this brand-new world, Martial Art is the way of life, and the strong set the rules.

Having awakened a Martial Soul of the lowest rank, possibly meaning he will never go far as a Martial Artist, Su Mo is determined to rise to the top again nonetheless.

However, misfortunes never come singly. The love of his life is soon taken by one of the most powerful forces in the world. With no time to spare, watch as Su Mo overcomes all odds and struggle on the verge of death countless times, in order to meet his love again.

As the protagonist reaches the top in that world, he has to take on more responsibilities and face new challenges.

Follow Su Mo on his relentless journey to become stronger for the sake of those important to him, and uncover the deep, dark secrets and plots in the vast universe.

- Description from Novelupdates