The law of Fiction: Harem in the fiction world - Chapter 20 Ch 18: Submit To Me [Pt2]

When Zhou Shu woke up, he learned that he had become a Forging Apprentice at a workshop in the Forging Division of the Great Xia empire.

In the tenth year after the new era, the world finally came to an end. Zhang Mu truefully waited for his death, but unexpectedly found that he had returned to ten years ago. With his memory about the future, he swore that he would change the calamitous history, saving the earth from being destroyed! Walking dead, zergs, evolvers, and various mutated animals… nothing can stop him! The first step is to retrieve his identity as an era merchant , then find all the treasures he can remember to enhance himself!

- Description from Novelupdates

The leader of the thousand demons, the Demon God Chun YeoWoon. Due to an unfortunate accident, he had been sent to the distant future.

The hidden dragon stirred from its sleep, the fierce tiger descended the mountain! Ye Wudao, following his master's orders, crossed into the mortal world, his medical skills so advanced they could reverse fate, his divine magic alone dominating the universe. Whoever dared touch my dragon scales, regardless of their power or status, was met with instant death!