MTL - General, You’ve Lost Your Inhibitor! - Chapter 59 big win

A pair of young girls that appear to be the same age act like a mother and a daughter. They are on a journey for one reason: to obtain a medicine that will stave off the daughter’s disease. Killing demons, deceiving people, and giving her everything in hope that there’s a way of rescuing her daughter. This is the story of their fragile hope and overwhelming despair.

For decades, the brave warriors of the Northern Army fought to keep the world safe from the evil Silent Night. But when the fourth-generation leader, Jin Kwan-Ho is accused of colluding with the enemy, he is forced to disband the sect and commit suicide to protect his son, Jin Mu-Won. With no family and allies left, Mu-Won leads a dreary life under close surveillance… until a surprise attack from the Silent Night gives him a chance to escape to the mountains.

There, the young warrior trains to master the fighting techniques of his predecessors, before the mysterious disappearance of a loved one brings him back to the mainland. Follow Jin Mu-Won as he embarks on a journey to avenge his father’s death and take down the villains who threaten to plunge the world into darkness!

It begins on the mountain.

With the glint of a knife, a flash of steel in the hands of a sworn brother. A betrayal.

Stabbed and pushed down the mountain, Zi Chen lied within the red-stained snow, left to die.

This is where it begins; he is given life by lightning,
baptized by thunder.

Those who had once betrayed him should all suffer in his cruel revenge.

- Description from Novelupdates

____this story sets in Japan that developed a little different history from yours.

This is how a Japanese Princess relieves her stress of the day by using the latest VRMMORPG, and while playing the villain there, the first town turns into whirlpool of chaos, smashed the underground organization in one hand and went for a coup. It’s literally a playtime diary of a girl who is called as “Genocider-san”, “Roaming Last Boss”, “A different person plays the game”, “Raid Boss”, “Ruthless”, “Calamity”, and such by the players.