Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 3 Chapter 2.3

A Betrayal of Fate--- Anos Voldigoad, a young man of noble spirit, faces a devastating turn of events. Betrayed by his own kind and the woman he loves, he’s thrust into a world of darkness and despair. His world shattered, his parents murdered, and his beloved forced into the arms of his sworn enemy, Anos questions the cruel hand of fate. As he succumbs to his mortal wounds, a final, haunting image lingers: the smug grin of his tormentor, taunting him with promises of his lover’s destruction. In his dying breath, Anos wonders: Why has God forsaken him? Is it because of his weakness, his goodness? As the darkness claims him, a seed of vengeance is planted, a promise to rise from the ashes and exact his revenge, no matter the cost.

Three years ago, the animals and plants on Earth underwent crazy and unexplainable changes that included transformations, reversions, and the addition of otherworldly species. And it was the start of a brand-new type of profession in the new generation of humanity – Monster Trainers, people who specialized in taming monsters.

When I opened my eyes, I found myself in a game where heroes and villains prevailed. I was told I would be granted one wish if I clear the game. The protagonist, who received a growth cheat that allows you to steal his stats by killing an opponent. He kills villains to grow up, but for some reason people mistake him for a “dark hero.” [Story-oriented]

One-eyed Wolf Lecan is a skilled adventurer who has conquered many dungeons all over the world. He had been going solo for a long time, but in the last three years, he’s had a partner. That partner jumps into the black hole together with Lecan, and both go their separate ways as they fall into another world. Dungeons and magical beasts also exist in that world. After learning the native language, Lecan goes on a journey. Meeting a good teacher, Lecan studies medicine making and magic under that teacher, and begins his dungeon explorations for real.