Era of Castles: Starting with 99 Dragon Eggs - Chapter 39

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates

When the last prodigy level esper on Earth disappeared, Earth was in deep trouble of becoming another species’ colony. The ordinary Han, with his intelligence and hardworking character, was able to make a fortune after “accidentally” stepping into the world of dark net, later purchasing an esper power crystal that brought him the ultimate power that changed the fate of the universe.

Jack Somnus was a mid-wealth professor of economics and a trading advisor for the powerful Johnson family. But after years of working for the Johnsons, he was abandoned without a word. He was laid off without as much as a severence package. Jack’s life got worse when he lost his wife. Depressed and alone, he got into an unfortunate accident. Instead of dying, he travels back in time to his teenage years. Now, Jack has a second chance to live the life he always wanted. He wants to be the one who controls, not the one being controlled. But his time travel hides a deeper secret, one that might throw him for a loop. [WARNING: CONTAINS EXPLICIT EROTIC SCENES]

Thousands of years ago, the great abilities of the three teachings of Buddhism, Daoism, and Demonism decided on a place for becoming immortal. Three thousand years ago, a Taoist was close to becoming immortal. Three hundred years ago, the Daqian Dynasty was established, and chaos is expected in another three hundred years. In this era, the path to immortality opens; a celestial swordsman freezes fourteen states with one sword, a heavenly Daoist maiden seeks eternal life, a naturally born Holy Son claims to be invincible, and a Buddhist Holy Monk saves all sentient beings.Gu Wen lives as a beggar, enters a household as a servant, witnessing the disordered world, drifting aimlessly.In a world filled with divine beings, he alone is a mortal.However, a lowly origin is not a disgrace; striving through the grand path, even as a common man and mundane son, he can still be the foremost in the world.“Mortal Gu Wen, my Dao is euqaling the heavens!”