MTL - Global Beast Taming: My Battle Pet is Double of Others - Chapter 115

Jian Wushuang was reborn in adversity. In order to get his revenge, he began to cultivate Heavenly Creation Skill. With the help of the Heaven defying cultivation method, Jian Wushuang gradually grew into a peerless genius from an ordinary practitioner. With a sword in hand, no one is his match. Using his extraordinary Sword Principle, he killed all his opponents and eventually became number one Sword Master from time immemorial.

- Description from Novelupdates

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

I couldn’t even clear the 2D version, now to clear the game in reality?Maybe I’ll have to live here for the rest of my life.Well, even that won’t be easy.– A player found himself in the game, Dungeon and Stone, as a savage barbarian.To keep his secret, he must become the mask – must make himself be seen as more savage, more fearless than any others – a paragon of his race in the eyes of the whole world.Back on earth, in the empty darkened room, the quiet computer again began to whir. Text began to appear on the black screen.「Synchronization complete. 」

This is a story about the protagonist getting the system, going crazy in the biochemical apocalypse, producing aircraft and tanks, destroying zombies, saving good people and killing bad people.

- Description from novelbuddy