The Ruler Of Darkness - Chapter 14Book 4:

【Urban edition of a passionate and exhilarating story!】I have set foot on the summit of the mountain, and have also fallen into the abyss!An extraordinary genius, returning to the city!

In this school fantasy story set in the distant future, creatures contaminated by pollution have overtaken the land, forcing humanity to live in isolated mobile cities called Regios. One such city named Zuellni is a self-contained school in which freshman Layfon Alseif has just enrolled. Layfon reluctantly joins the 17th Military Arts Platoon led by the third-year student Nina Antalk and embarks on a series of adventures.

In this world, Planet Earth had undergone great changes and humanity is faced with extreme danger. Luckily, humans have something called the Heaven Dao software.

On modern-day Earth, An Lin seems to have been abandoned by God.
When his father suddenly disappears, An Lin is left with his father’s immense debt, putting his life at risk.
After being forced to a rooftop by his pursuing creditors, An Lin is unexpectedly swept off his feet and brought to the ground safely.

After learning that he was saved by an Immortal, An Lin is gifted, seemingly out of pure generosity, the ‘God Of War System,’ and a pass to a new realm.
Follow An Lin as he experiences a whole new world of legends, meets many new friends, acquires legendary weapons and tools, and starts on his path of becoming a powerful cultivator. There is never a dull time in An Lin’s new life with his ‘great’ new system!

- Description from Novelupdates