Hell's Handbook - Chapter 391

Aomori, who has a monster-fighting system, came to the world of One-Punch Man and gained the ability to enter various instances.

Therefore, “Founder of the Hero Association”, “NO. “And other titles fell on him one after another.

Comprehensive flow, the main world One Punch Man.

Completed dungeons so far: Pokémon – Demon Slayer – Sword – Pokémon – Digimon – Spell Return – Yokai Comprehensive World (Girls that Noragami Inuyasha can see, etc.) – Pokémon – One Piece-re0-Dragon Ball wait.

- Description from novelbuddy

Each stroke of good luck is a triumph over someone else’s misfortune.Jack Grim, the son of two legendary assassins, was born and raised on nothing but coldness — and the skills to spill blood.At seventeen, Jack received his final task as an assassin apprentice under his parents.“Succeed, and you’ll run your own organization — live the life you’ve always dreamed of.”For Jack, it was everything he had ever wanted: the chance to finally become the professional assassin he was born to be.He struck his target at midnight, succeeded, and received everything his parents had promised.But in the wake of victory came a pounding headache, a relentless fever—and then… transmigration.Jack now found himself in Raiden’s body — the keeper of the Book of Ashes, the heart of the Devourer, and the very book the coward Raiden had died protecting with his life.Jack had no desire to live in another world, magic or not. He simply wanted to return to his life as an assassin.But duty had other plans. The balance of this world now rested on his ability to protect the book — and like it or not, the responsibility was his to bear.

The moment when mercenary leader Kwang Hwi receives video game like abilities, the world is suddenly thrown into chaos. A thick fog envelops the Earth, bringing with it savage, otherworldly monsters. At the same time humanity has been rendered defenseless against this onslaught, as the strange fog turns most weapons to rust. With mankind spiraling towards oblivion, it is up to Kwang Hwi, with his new abilities, to save the world. Watch as Kwang Hwi leads his militia and becomes the last bastion of humanity. Will he be this world’s savior, or its conqueror?

A young boy named Chen Zong got lucky and found a mysterious Sword Seal. With the help of it, he rose to be a God in Sword who defeated innumerable top talents in all universes from a remote borderland.

- Description from Novelupdates