Skill Creation in the Fantasy World - Chapter 138: Volume 2- The Guild Wars: Start of the War.

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.

Zhou Wenwen, who had traveled to a parallel world because of sudden death, thought that he could only live in such an ordinary life in this life, but the golden finger finally opened. He has a store where he can buy technological items and magic equipment to ensure his survival.

But the threat that followed made him realize that this place is not ordinary, because there are Transformers, Marvel, the Dark Portal from World of Warcraft, etc.

- Description from novelbuddy

Depth-Dwellers are long extinct.All except for a single one..Waking up after being dragged by the pressuring tides, Cetas finds himself in the middle of an unfamiliar ship, greeted by a distinct group of pirates.Without any knowledge about humanity at all, he traverses the seas with the unknown band of pirates and learns about their culture and speech. In a world where 'Zeal' serves an essence for humanity's power, Cetas must learn to ascend the ranks to protect those that he cherishes.For when the mysteries beyond the fog arises, the Dreadspawns begin to wreak havoc, and the Leviathans rise up into the world..'Would Cetas become a 'human' worthy of saving those that he loves?'

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.