Epic of Vampire Dragon: Reborn as a Vampire Dragon with a System - Chapter 89: Conquering The Boundless Abyss Dungeon, Becoming A Great Dungeon Master!

Anyone who could construct a stable Spell Model could become a Wizard — that was the Wizards’ ultimate secret! Having been given a new life as the son of an aristocrat and armed with a super quantum computer from his past life, Spell Models came as easily as breathing to Merlin. With this overwhelmingly huge advantage, would Merlin become the greatest Grand Wizard of all time?

- Description from Novelupdates

He became Arthur. He lived his life as Arthur and claimed Excalibur.Now, he has returned with a purpose.Beneath the surface of the world lies a twisted world known as the veil—an dimension where monsters are born from corrupted human emotions and desire. The deeper you go, the more terrifying they become.Each Layer is sealed. Each hides a god-like being, waiting to rise to the surface.Now, Sylas bears the responsibility of keeping the gate between both worlds from breaking.[Keys are passed down through generations.No one knows where they came from, but those keys can open doors to another world — a world filled with deadly trials. If you complete the trial, you return with blessings from gods, mythical beasts, and ancient warriors. The amount of blessings you earn depends on how well you perform.But if you fail, the door shatters… and you are gone forever.If you survive, you are given a permanent rank — a rank that decides your place in society for the rest of your life.]

Of the ancient gods only one remained in the world. This god lived alone for thousands of years and no longer had any desires. Legend had it that during the great war between the worlds he used his powers to turn the tide managing to seal the cataclysmic rift bringing order back into the three realms. Time flew by and hundreds of years passed in the blink of an eye.

A back-to-basics(?) monster evolution novel.