Isekai Maou to Shoukan Shoujo no Dorei Majutsu - Volume 2 Chapter 1.06

A striking man of mysterious origin and peerless talent, he looks back at the world, in all its entirety, with utter disdain. And yet, in the treacherous and unpredictable ultimate formation of the Boundless Secular World, he guards a breathtaking ancient qin with broken strings, waiting silently for the destined one to arrive!

After coming out of a tunnel… it was pitch dark.

Yang Feng somehow transmigrated into a different world and received a legacy of an ‘ancient high tech’ family, which does not directly raise his power, but gives him the technology to build things which are way more advanced than the seemingly medieval world.

But to build something you need resources and energy. To receive resources you need strength. To gain strength you need knowledge. To gain knowledge you… need strength? or a background? Or maybe a fully armed army of high tech robots who aren’t afraid of death?

But is this legacy really for him to keep?

- Description from Novelupdates

Kiyoshiro Takeda lived a life without purpose, drifting through his days with no direction. But one fateful moment changes everything. Now, he finds himself in a world unlike any he has ever known, given a role he never asked for. A new life, an unknown destiny, and a looming catastrophe that only he can prevent. But can someone who failed in his old life truly become the last hope?