Shrouding the Heavens - Chapter 9: The 30th Person Inside the Bronze Coffin

What happens when a fanfic author with a habit of lying and scheming suddenly finds himself as a self insert during Duelist Kingdom? What happens when you have Yugi, Joey, Kaiba, and the rest encounter someone who knows all about every major player in their saga... and sees no problem with abusing said knowledge? Chaos, dear reader. Sweet, sweet chaos

This is the story of a man who had no choice but to become a villain.But not just any villain because even villains have standards.This is the journey of a man learning how to become one. And to help him, the MC has access to an unlimited number of villains in his System Space, pulled from across all realities from every known dimension: Murim, Cultivation, Supernatural, Urban, Martial Arts, Mecha, and beyond.So what is it that Razeal can learn?What can he teach? And why?How can someone with knowledge from nearly every kind of reality reshape the one he’s living in?Someone with the potential to access everything the multiverse has to offer?Tired of seeing the same ideas repeated?The same system copy-pasted with no soul?No real character building no personalities, no free will?Come read this.Who knows you might find something worthwhile.

This novel is also known as Don't Mess with the Dark Princess

When trash becomes a genius—one word: Fierce! Two words: Two-faced! Three words: Too heaven defying!

She is the foremost and outstanding armament refining master. Passing through a dynasty, and became a publicly humiliated and bullied Third Young Miss. Ancient beasts, too outrageous? Obediently become a docile pet, or I’ll make you into soup!

Ninth rank talent, rare talent in a thousand years? She was born with a godly constitution, crushing all geniuses!

Peak level Profound Grade Armament, beyond priceless? Sorry to embarrass, but the bowl she uses to feed the cat is already at the God Grade….. she possessed a pair of eyes that could see through everything, yet she couldn’t see through—him!

Merely exposing his demonic smile, Prince Mou lightly loosened his belt: “Can’t see through? Do not fret, you can slowly view when you return to the room. I’ll allow you to scrupulously inspect from head to toe.”

- Description from Novelupdates

I finally managed to kill the demon lord.