Katahane no Riku - Chapter 52.The main character

Yun Luo Feng, Hua Xia Medicial School’s genius, died from an accident and her soul attached to Long Xia mainland’s General family’s useless eldest miss.

Crossing into another world, Shen Yuan unexpectedly picks up a mysterious Turtle Shell in the river, activating the [Daily Hexagram] system bound to his family.[Today's Hexagram · Auspicious]: You pass by the Black Water Pool and unexpectedly encounter a Centennial Blood Toad shedding its skin. The shed skin has extremely high medicinal value and can be sold for two hundred Patterned Silver taels.[Today's Hexagram · Great Ominous]: A Barbarian Race scout team sneaks into Hidden Dragon Mountain. If you go into the mountain to chop wood, you will encounter bloodshed.[Today's Hexagram · Auspicious]: You take your son to hunt in Hidden Dragon Mountain and will have a good opportunity.[Today's Hexagram · Great Auspicious]: You spend a fortune to purchase a piece of land from the County Government, which hides a Lower Grade Spirit Stone Ore Vein.

After Wang Mang died, he turned into a giant python and evolved like crazy!

With the help of his family, he grew bigger and bigger! From the first few meters to tens of meters, and then to hundreds of meters!

From Burmese Python to Titan Python, and then to Deep Sea Python! When Wang Mang’s size reached hundreds of meters, the earth took a sudden change and the disaster came…

There was once an immortal cultivator fighting for the fate of human beings. Unfortunately, he failed that time; but fortunately got another chance as he was reborn once more as a human, on the earth of 5,000 years ago. With a second chance, he not only would embark on the road of saving all mankind, but also would retrieve his human nature on the new journey that would last for 5,000 years.

- Description from Novelupdates