Hero? I've Long Stopped Being One - Volume 1 Chapter 4

A veteran gamer finds himself in a world similar to the game he played.You say you need to learn skills by leveling up? Sorry, I already know all of them.You say you have to meditate to level up? Sorry, I only need to fight monsters for that.

In a modern world where cultivators need a place to cultivate or vent their boredom, there are private businesses that set up instance dungeons with the aid of technology and cultivation magic to enable cultivators to train and commoners to experience the life of cultivation. They are called dungeon suppliers.
Xie Jin's one and only dream was to be a dungeon supplier and when his only relative passed away, the relative's inheritance gave him a plot of land and surprisingly, a 'System' Module which the relative had previously used.
With the help of the system, Xie Jin decided to pursue his dream of becoming the number one dungeon supplier.

Lucifer travels to the world of One Piece, binds the system, and obtains the fruit of words and the power of hell demons at the beginning.Everything Lucifer says will become reality, and matter can be summoned or generated through sound.Flash, lightning, fire, ice, magma, gravity, earthquake, all powerful abilities, Lucifer can use.By beheading enemies, Lucifer earns kill points, which buy more powerful powers.Akainu: As soon as Lucifer speaks, my magma can only be used to light candles.Kizaru: As soon as Lucifer opened his mouth, my flash was slower than a turtle.Whitebeard: My Shock Fruit can't shake a rock.Kaido: My immortality has failed.Redhead: Why is my strongest Conqueror's Haki gone?Five Elders: Please, stop talking.Lucifer: I haven't done it yet, why are you so stupid?Everyone: You didn't do anything, but you did.Lucifer: A gentleman uses his mouth but not his hands.From then on, a hell demon who used his mouth to attack invincible opponents all over the world was born.Disclaimer: This is Translation

The novel is about an author who was reincarnated into his novel.This author thought that he would become a hero, like he always wished, but no, his fate was to become a Villain.His fate was to fight against humanity and against the supreme beings who were planning to invade the world.