Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 6 - 6-1. I Want to Practice Magic [Failure Arc]

In a world where the strong prey on the weak and nobles slaughter commoners like insects, Alex was just a weak boy who lost everything to the cruelty of fate.For the sake of revenge, he rose from the ashes, determined to carve his path through a world soaked in blood and betrayal.But there is something the world does not know—something even Alex himself has yet to discover...A power buried deep within his blood, ancient and untamed, waiting to awaken.

The weak prince of an insignificant country, Davey. After becoming comatose, his soul escaped to a temple where the souls of heroes gathered.

He trained for a thousand years and has now returned as a max level hero!

“Just you guys wait, I’m gonna face you all head-on!”

The refreshing story of Davey’s royal life and revenge has just begun.

In novels with a stud there is always a Senior Martial Brother like this:

In the early stages of the novel, his innate talent is high, his cultivation is good, his appearance is handsome, and he has an intelligent, cute younger Martial Sister as a fiancée.

In the middle stages of the novel, he is caught unprepared and defeated by a young disciple (the protagonist) in the sect who’s hardly remarkable at all. From then on, he falls from his godly altar and loses his brilliance. Even his young Martial Sister leaves him for someone else.

In the late stages of the novel, he continues to turn dark, going down the Demonic Path and becoming the major villainous boss. However, the protagonist still ruthlessly defeats him and his soul is eternally sealed.

Once Qin Mo opened his eyes, he discovered that he had become this Senior Martial Brother.

- Description from Novelupdates

The moment when mercenary leader Kwang Hwi receives video game like abilities, the world is suddenly thrown into chaos. A thick fog envelops the Earth, bringing with it savage, otherworldly monsters. At the same time humanity has been rendered defenseless against this onslaught, as the strange fog turns most weapons to rust. With mankind spiraling towards oblivion, it is up to Kwang Hwi, with his new abilities, to save the world. Watch as Kwang Hwi leads his militia and becomes the last bastion of humanity. Will he be this world’s savior, or its conqueror?