Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 16 - 16-80. God Keys

In the rebirth, in order to prevent the tragedy of the previous life from happening, Bai Yu decided to rush to the [Tower of God] at any cost, and face everything together with his sister!

However, Bai Yu, who was bound by the system, mutated his bloodline, and transformed into a black-scaled python seems to be developing on a completely different path from his previous life…

- Description from novelbuddy

The Northern Ice Fields had no boundaries.

The Winter Wolves hid within the snow, the Frost Tigers growled incessantly, and the roars of Giants echoed throughout the land. Many species struggled to survive in the icefield. At the same time, a baby White Dragon possessing the power of time broke out of its egg and opened its platinum-colored eyes.

Years later, the legendary Time Dragon appeared, moving freely between the endless past, present, and future.

Freshman student Yang Dingtian possesses the Nine Yang Body, found only 1 in million. His Yang Fire is incomparably vigorous and thus, he cannot be near a female’s charms for his entire life. On the night of his 19th birthday, he decided to bid farewell to his virgin life. After stealing and tasting the forbidden fruit, he spontaneously combusted as the result!

In death he crossed over to another world; a world that held respect for Martial Power. His, originally, catastrophic Nine Yang Body was the Nine Yang Body that couldn’t be seen in a millennium! He was saved by a mysterious old man when he was at his last moments and the old man received him for a disciple, then betrothed his daughter to him. Thus, in this odd way, Yang Dingtian became the successor of the largest clan under Heaven, and became the number-one-beauty-under-heaven’s fiance.

- Description from Novelupdates

Synopsis one: “The people here aren’t innocent. They’re cunning, they’re greedy, they’re ruthless.” “The nobles here aren’t noble. They’re selfish, they’re arrogant, they’re schemers.” “I was once furious about this. But now, I just pity them. This is a dark world, from the moment they were born, they had no choice but to live life like this. Now, I will give them a choice.” “I want to bring them food so they can be freed from hunger, that will give them morals. I want to bring them peace, so they can have beliefs. I am a transmigrator who has come from a faraway world, I want to bring the fire of civilization to this dark and barbaric place. I know I’m doing the right thing. Eliminating hunger, eradicating plagues, suppressing evil, and ending wars. I will give a second chance to anyone who wants change.” “Then, I’ll kill all of those shameless, brainless idiots.”

Synopsis Two: Kang De transmigrated. He didn’t expect this new world to have sorcerers, dragons, and even gods who were mythical beings that only existed in legends. To protect himself, Kang De had no choice but to train and fortify his body consistently. Soon, he realized that malicious intent didn’t just come from those who possessed extraordinary powers, but also the greedy aristocrats and the king, who was a ruthless dictator. “What? Did I overthrow the nobles? I just wanted to lead the people in my territory to live better lives?” “Why are you guys calling me the king? I don’t want to be a king!” By the time Kang De realized what was happening, his territory had already become the most powerful human kingdom on the continent. The Dragon Emperor called him a brother and powerful sorcerers formed his army. The only targets left now were those gods who saw themselves as superior beings!