God of Death: Rise of the NPC Overlord - Chapter 45 - 46: Godslayer Protocols

A genius inventor dies and awakens in his younger self's body... but not quite. This isn't his original younger self-it's an alternate version from a reality where the supernatural is real.To make matters even more chaotic, he discovers that someone has decided he is the successor to Solomon. Now, he possesses the power to enslave devils. Armed with his intellect and newfound abilities, it's time to spark a worldwide revolution... starting from his garage!---Tags: Neutral-Evil MC (enslavement, selfish MC), Harem (of course), Inventions, Technological Progress, Sacred Gear Creation, AU DxD Universe (part of Dragon's Omniverse).This fanfic is a STEAMROLLER, with the main focus on the MC's development and his technological innovations, as well as their impact on the world. If you're looking for drama, suspense, or epic battles with no real purpose, this isn't the story for you.

In previous life, I was just a mediocre guy, and accomplished nothing.

After reincarnation, I seize the opportunity of being a legend of the times. In this life, I am the protagonist in Tianxuan World, a great master of martial arts and a founder of making elixirs. What? You want to compete with me in weapon and equipment refining? Then, you should know the Craft God is my disciple…

- Description from Novelupdates

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.