Lazy Dungeon Master - Chapter 561

Ryouma Takuma, a 39 year-old man with a hidden past, finds himself in a strange white room. There the gods tell him that he has died and that they are sending his soul to a different world; a world where magic exists. After living alone for three years his gamer soul loses common sense and starts toward crazy routes.

An underachiever, a chance accident. He gained the premier Cultivation Technique, and from then on, his fate was completely changed.Cultivating superpowers, protecting the campus beauty! With overwhelming strength, he swept through all formidable enemies and made the world tremble with his military might!This is a tale of world conquest! It is also an unbeaten, fiery legend!

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