Shinwa Densetsu no Eiyuu no Isekaitan - Volume 3, Chapter 2 – A New Mission, Part 3

“I'm sorry, Kiara,” he began, his voice heavy with regret. “We regret to inform you that we can no longer administer these drugs to you.”I was dying. I was going to die.Kiara Williams was dying from Stomach Cancer. With only a few months to live, she could only stay at the hospital.Alone. Her annoying husband did not come and visit her, only her best friend, Jessica remained by her side. She could no longer pay the bills and was sent home.Arriving at her house she caught Jessica and her husband together in bed. In a fight, her husband pushed Kiara down the stairs.Kiara died.Or did she? She was reborn ten years back, but rather than being destroyed, she begged a strange man for a one night stand unless she may die again.

Adrian Voss was a forgotten beta tester—erased by a corrupt game company that put profit over players.Now reborn in Primordial Abyss with a glitched class that lets him control dungeon bosses, he doesn’t grind levels… he grinds players.Every monster he subjugates becomes a weapon. Every raid boss he enslaves earns him passive income. And every overconfident guild that steps into his domain?They drop loot when they die.But this isn't just another OP power trip. Adrian doesn't win because he's stronger—he wins because he's smarter. He lays traps like a raid leader, exploits mechanics like a dev, and rewrites the system from the shadows.From dungeons to PvP, he turns the most advanced gaming system ever built into a weapon that stabs its creators in the back.Now the streamer assassins, sponsored guilds, and even the developers are hunting for the one they call...The Dungeon Phantom.Too bad they don’t realize:The real dungeon isn’t the game.It’s the one they’re walking into.Let the hunt begin.

Mu Yue traveled to the world of Naruto and became an ordinary chuunin teacher at Konoha Ninja School and a member of the Root Organization.

Fortunately, after awakening the teacher system, you can become stronger by teaching.

In order not to become Danzo’s consumables, Mu Yue worked hard to teach and increase her strength.

“Complete the teaching rated A for the first time and receive the reward – mastery of fire attribute chakra properties change.”

“Under your guidance, Uchiha Shisui has worked hard to practice, and his overall strength has been greatly improved, and he has been rewarded – the Immortal Human Body!”

Under Mu Yue’s guidance, Zhishui understood that the village’s enemies were not necessarily other big countries, but could also be within the village. People who spoke righteously about the will of fire might not necessarily act in accordance with the will of fire.

Obito got rid of the title of being the weakest person in the ninja school, and Metkai became a master of physical skills even earlier…

- Description from novelbuddy

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.