Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 10 Chapter 4 part3

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

In the tribal farming era, the world was vast and unknown. Upon continuous exploration, the people of ancient times were appalled to discover that in this world, where the sky was round and the earth was square, all sorts of miracles had befallen them. There were even figures like an ultra-big ten-thousand-foot giant, as well as huge intelligent beasts that had mysteriously appeared, trampling upon the mountains and rivers, and shattering the earth. Hundreds of years later, in such a dangerous environment, people fought against the huge beasts and finally established the glorious Sumerian civilization. On this day, a wise giant suddenly made a complete descension on earth, trampling on all the mountains and rivers, and wiping out the entire nation. The world crumbled, and city-states collapsed; had the gods descended to condemn the people?

“I’m sorry, you’re all just ants living in the orchard of my yard and you are just scrambling all over the place. If I were to accidentally pass you by, I might just accidentally trample you all to death. That’s it for you.” So first, I’ll set up a sandbox in my own yard, a base area for plotting farmland. Then, I will shepherd the human race and various worlds in my sandbox.

Sold by her own grandmother to become a shared wife to the poverty-stricken Ye brothers for twenty taels of silver, Liu Duo, unwilling to succumb to her fate, escaped in the night. She slipped and fell and died an inexplicable death.

Demons, devils, ghosts and monsters

Plunge the mortals weak in horrors;

Arms of gods and blades of devils,

Shroud the world in untold evils.

Lu Sheng was an ordinary civil servant in the modern world. After waking from a drunken stupor one day, he found himself trapped in a dangerous world where demons, ghosts and supernatural monsters terrorize the land.

In this world, ordinary mortals live in dark fear and helplessness, without any means to fight against the supernatural.

As Lu Sheng struggles desperately for survival, he stumbles upon a game mod he had designed for a mobile phone app in his previous life. It unexpectedly becomes his special ability, which enables him to instantly level up any skill he learns, albeit at a cost.

Thus, Lu Sheng begins his journey, striving for power beyond the reach of a mortal as he treads the way of the Devil…