Ember Dragon - Chapter 275: Carnage

A next-generation virtual online game, a hardcore gamer, a glitch that shouldn’t have existed… By sheer coincidence, Meng Jingtian ended up being the sole player god in a game. Thus, while ordinary players worked themselves to death running missions for NPCs to win their favor, NPCs prostrated before him! While ordinary players almost vomited blood grinding for gear so that they could solo bosses, the king of divine beasts kneeled before him, willing to offer its life and worship him. And while players went to suicidal lengths to trigger random events and lucky encounters, transcendent beings came to find him so that they could offer their precious treasures as tribute.

Chen Sha came to a world of immortal martial arts and was ordered to take charge of the world’s first sect.

Before his death, the previous chief told him:

“If you don’t become the best in the world for one day, you are not allowed to go down the mountain for one day.”

So he closed himself in painstakingly, crossed the heaven gate in his body, and faced off against the ancient and modern powerhouses…

…

Many years later, Chen Sha recalled the day he went down the mountain,

From the moment he descended the mountain, he was number one in the world.

In the next ten epochs, any gods and demons have returned, immortals and Buddhas have lived in the world, ancient powers and ancient gods have appeared one after another.

No matter how the times change, he has always been No. 1 in the world and has never changed.

- Description from novelbuddy

After the nuclear warfare, massacres started to spread throughout the entire world. The order between humans completely collapses, and the strong eats while the weak gets eaten becomes the #1 rule.