The Sacred Land Is Going Bankrupt, I Invented a Mobile Phone! - Chapter 6: Immortal Artifact as a Server!

When Li Xianyu was 20 years old, he received his father’s inheritance, an 18-year-old great-grandmother who was incredibly beautiful.

Li Xianyu: “Great-Grandma, why are you so young?”

Great-Grandma: “That’s because I died when I was 18 years old.”

- Description from Novelupdates

What the heck? She, a famous doctor from the 23rd century, turned into a village peasant girl of a different world!

Kiro is a slave branded with a deadly collar, forced to work in brutal mines under the ruthless Kargal Empire. Each year, slaves are hunted for sport in the deadly Hunting Games—a fight to the death on a savage alien moon. This year, Kiro is chosen to play. Sent into a wilderness filled with monsters and traps, survival seems impossible. But something ancient watches from the shadows—and it has plans for him.