The Yu Brother's Case Book - Volume 1 Chapter 11.1

Returning to the Mysterious Era features a boy who can time-travel back to the past using old relics. The twist? He’s stuck in the body of the relic’s owner.After a near-death experience, Cassius unlocks his ability to travel to the past in the body of Li Wei, a member of the Wind Elephant Sect. Li Wei was a coward who lived a life of regrets up until the day the entire Wind Elephant Sect was mu*dered. As Cassius relives Li Wei’s past, he makes different decisions to show Li Wei a different kind of future.By living out the ups and downs of Li Wei’s life, Cassius is introduced to the world of Covert Martial Arts, ties that run closer than blood, and supernatural forces. Crossing the line between the ordinary and supernatural, he realizes there’s no way back. New friends and enemies slowly integrate into his reality.Now, he must uncover the secrets of Covert Martial Arts and get stronger to survive.

Humans across the world ended up joining a “Demon Kings and Heroes game”.

Several billion people were set down upon another world to act as “Demon Kings” and “Heroes”. Everyone has to chose their starting races from the start.

Zhang Nu was set in the Demon King camp.

He discovered that he could see hidden information that no one else could.
[Slime Demon King]. Low grade demon king bloodline… Not recommended!
[Kobold Demon King]. Low grade demon king bloodline… Not recommended!
[Dark Elf Demon King]. Mid grade demon king bloodline… Can be selected!
[Bloody Giant Demon King]. High grade demon king bloodline… Recommended!
[Abyssal Dragon Demon King]. Strongest starting bloodline… Extremely recommended!

I freed the Slaves, but for some reason, they keep chasing after me.

The best way to declare war on a spy as an ordinary person is to become a spy as well.As a spy, if you want to go to war with a powerful espionage organization, join an equally powerful espionage organization.If you are unable to join any powerful espionage organization, then establish your own espionage organization and fight until destruction or victory.This is the war of spies, telling the story of how a group of ordinary people achieved extraordinary success.