Shadow's Oath - Chapter 25

As he woke up, Wei Xuan realized he returned to the day when the apocalypse had just begun. Wei Xuan, who had a second chance at life, immediately decided: not to go to a survivor base, and not to return to human society, instead, there is only one thing he wants to do now. Find the half-zombie Du Hang, and live with him in the city full of zombies, farming and living together until old age. Wei Xuan, who stayed in the zombie city after being reborn, unexpectedly found out that zombies are not as terrible as humans think…

- Description from Novelupdates

Through a mysterious portal, Chen Jin arrived at this strange place – a post-apocalyptic world where civilization had been destroyed.

Consequently, he found –

A piece of metal scrap
A robot trash collector
A battleground
A city
A ton and more of gold
A copy of high-tech documents
A…
In short, Chen Jin found a planet.

- Description from Novelupdates

I want an S-Rank skill too! I want it so badly, I could die for it![You have awakened an S-Rank skill.] [But it only works when you die.]Eh !? WHAT IS THE POINT OF GETTING ONE IF I DIE !?