Wortenia Senki (WN) - Volume 5 Chapter 20

Ukei Kaito fought a desperate struggle in order to fulfill his role as a summoned hero. He defeated the Demon Lord and saved the very world, only to meet an end filled but with betrayal. The companions that he’d trusted throughout his journey betrayed him and killed him by sticking a blade through his chest.

She fought in the Battle of Changping and witnessed the killing of hundreds of thousands. She once led the Qin Iron Calvary and battled against the Six Kingdoms. She has seen a third of the land and witnessed the breaking of mountains and rivers. The sound of a grand zither and the light of a great female emperor. A prosperous world that was forged on the battlefield. Yet, these two thousand years are forgotten from history.

- Description from Novelupdates

When a person dies, they either die light as a feather (aka unimportant) or heavy as Mt. Tai (aka very important).

11-year-old Jung Si-woo always had to play alone during PE class.

“I’m excluded from any ball games.”

“Are you kidding me? Why are you the only exception?”

“If I play with the rest, everyone will be excluded. Physically.”

The strength that Jung Si-woo has is not from any hard training but just a power he was born with.

When he turns 16 years old, the world faced a cataclysm, a huge castle appeared over the Earth out of nowhere. It began selecting special humans to grant them wings making them a Player and that soon changed the world.

10 years passed.

Jung Si-woo with a supernatural strength has still not been able to forsake his dream to be a Player. While he was enjoying his jobless life, he saved a falling Player and unknowingly met the requirement to be a ‘Underground Player’.

He became more special than anyone ever is! Now, Jung Si-woo brilliant dungeon strategy play begins.