MTL - The God of Sky & Earth - Chapter 17 : Adding light to the city.

A man who was once called the world’s strongest agent ended up becoming a teacher after his retirement, to train a new generation of agents. After many years of training his disciples, he was killed at the age of 60 by a secret organization’s ruse and was reincarnated in another world with his memories intact. Though he was surprised by the existence of magic and the strange species in that world, he quickly adapted to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his rigorous discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life. This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.

Five years ago, Gu Jiayu, who climbed out of the mountain nest, entered the entertainment circle in order to cultivate, and in order to overcome the shortcomings of emotional gaps, he used an excellent acting skill to hook up a Chinese “little nobleman” abroad. After a month of falling in love and feeling love, he ran away with guilty conscience after the other party proposed marriage.

Five years later, Gu Yingdi had become popular all over the country, but he had a four-year-old son beside him. 

One day, the little handsome guy pointed at the man who took up the entire page in the financial newspaper and said, “Dad, this man looks like me!” Gu Jiayi glanced at the calm, handsome man in a suit and shoes in the newspaper, and asked with a guilty conscience, “He has an onion head, and his body is black and black like the top post. Are you sure you look like him?” That night, “Top Door Post” came to the door … Gu Jiayu, “My son, hide your tail!”

- Description from Novelupdates

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.

The status of a wizard is transcendent in all continents and in the universal plane.