One Piece: Fist of the World - Chapter 40: The Navy’s Attack

The Jiuzhou Continent contains an era of chaos and fiendish demons, haunted by mysterious beings and fraught with feuding martial families, demonic sacred grounds, and endless struggles between various powers. Conflict is a constant throughout the world.Within such darkness, Gu Chen opened his eyes to this reality.At the same time, he discovered that as long as he slew these fiendish demons and ghosts, his cultivation strength could continually elevate.Killing a Panic Level Demon yields a decade's worth of cultivation.Slaying a Ghost Level Fiendish Ghost brings thirty years of cultivation....Eventually, one day, staring at the endless swarm of fiendish demons and world-renowned grandmasters in his path, Gu Chen chuckled lightly, “Are you able to withstand this fist of mine, charged with 1600 years of cultivation?”

The only being with extraordinary powers on Blue Star has mastered the Gatling Flight, turning missiles into flying swords. His short-term goal is to destroy planets using psychokinesis.

“Did you know? I was once the most powerful person in the world, undefeatable even by the gods. If only I can retrieve my body, I could resurrect once again.”“So what?”“So... who has hidden my corpse!”

In a world where dungeons were an essential part of it, Rein was trying to conquer as many as possible. They were the key to gain powers in the fastest possible way. So, to reach his full potential and to become the strongest, he became a great dungeon conqueror.With his trusty friends and lovers, he was definitely going to reach the peak alongside everyone. Join Rein and see how he went from strong to stronger and then the strongest.__________________1. The harem would not be too large(I'm not sure how many but probably just 4-5 main and few other here and there). All the girls would be getting their time and story.2. The story is starting when the MC is in the middle of his growth stage and not at the very beginning. But his beginning will be mentioned in the story in some form.3. I don't think I need to mention this, but obviously it will not have any NTR, rape or that kind of stuff. It is actually quite a wholesome story focusing mainly on adventure, action and bit of romance and slice of life.