MTL - Fox in the Penalty Area - Chapter 136 the meaning of failure

Condition 1: One yellow scarf soldier rune is satisfied

Condition 2: Kill 100 rune monsters independently

Condition 3: 5,000 times of training to kill a pig with a knife is satisfied

Condition 4: 10 Spirit Talisman Pills are satisfied

Rune unlock upgrade.

Your source runes have been promoted from ordinary quality [Yellow Turban Soldiers] to premium quality [Yellow Turban Warriors]!

- Description from novelbuddy

Leon was once an ordinary man—until he died saving children and woke up in a new world as the last prince of the demon race. But his awakening comes with a cruel truth: the war is already over.The Demon King is dead. The once-mighty demon empire lies in ruins. And now, Leon stands amidst the ashes, surrounded by a handful of survivors teetering on the brink of extinction.Crowned Demon King by default, he holds the title—but there is no kingdom left to rule. The few remaining demons are barely surviving, hunted and outnumbered. Worse still, Leon, who once enjoyed the luxuries of modern technology, must now navigate a harsh world stuck in the Middle Ages.Can he pull the demon race out of their misery? Can he reclaim the power they once held? Or will history remember him as the last king of a fallen race?Follow Leon on his journey to rebuild, conquer, and defy fate itself.

The tale of Oliver.
An orphan boy from a Mine, in 19th century Europe, filled with Magic.

The protagonist travels through Shu Mountain and becomes a demonic dragon guarding the heavenly book in Dinghu Peak.