Romance of Dragons and Snakes - Chapter 193

An underprivileged prodigy, a cruel, ruthless world, and an epic story of battle and conquest. A young man with an exceptional inheritance leaves the small, rural city from which he hails on a journey to find the girl of his dreams. He defeats countless prodigies, sweeps through all forces that dare to stand in his way, and progresses step by step toward the pinnacle of all the worlds!
“I’m not targeting any gods in particular. All I’m trying to say is that all gods are trash in my eyes!”

- Description from Novelupdates

“Future Occupation…Demon King.”

Sai Akuto enters Constant Magic Academy to be useful to society and to become a top-ranked national magician. However, a horrible prediction is made on his first day. Thanks to this prediction, the class representative girl hates him, a girl with a mysterious power embraces him, a female artificial human is sent by the empire to observe him, and his school life is otherwise thrown into chaos…

[You have awakened with the Lifespan Extraction System!][Extract Lifespan, advance your Cultivation and Cultivation Talent, amass an unstoppable Army of Shadow Beasts, and ascend to the Pinnacle of the World of Immortal Cultivation!]In the Super-Continent of Legaria, a Godlike youngling was born… and abandoned.Scorned and hated by all for merely existing, Zar struggled day in and day out, just trying to survive to see the next dawn. In a world of Intelligent Beasts, he, a Half-Beast, Half-Human—a species alien to the inhabitants of Legaria—had no one to rely on.By some miracle, he managed to make it in one piece to his 15th birthday. A day… which changed everything for him.*Ding!*[Are you ready to become the Ultimate Immortal Beast Tamer?]Fate shall be rewritten!Zar—a lone Godling—shall rise up and make even the most arrogant of God Beasts and Immortal Cultivators relinquish their strength to him!

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