MTL - Rebirth Starts From 2006 - Chapter 792 explain

A fighting genius.

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.

Among the demons, the supreme ones are called “Great Saints.”

A young man leaves his mountain village and travels around the world. By unceasing efforts, he finally becomes a legend of the age.

- Description from Novelupdates

This novel is also known as Fey Evolution Merchant

The shining stars and birds flying in the blue sky and white clouds, the fast shadow clouded leopards hunting and hunting in the vast grasslands, the acid eroded pythons hiding in the shadows of trees in the mottled rain forest, and the chalky Canglong dragon under the deep blue sea.

Lin Yuan found that he could allow infinite evolution of spirits, and continuously purify the bloodline.

Dust butterfly-stainless steel butterfly-emerald green butterfly-royal tourmaline butterfly.

This is a pure pet article, a world of beast masters.

- Description from MTL