Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 4 prologue

An ordinary student, a wretched peeper, a cowardly teenager with a kind heart. In a terrorist attack, he inherited the knowledge of countless elites, embarked on a path of God Jagged Tu…

He is an artist!

He is a mathematician!

He is a psychology Doctor!

He is a master of fighting!

In fact, he is a man

Taken off raw site:

A wretched, dirty young man is working during the summer when he was caught up in a mysterious explosion. After that explosion, the young man is then left with the memories and knowledge of dozens of the world’s experts.

He has changed, his heart has become cold, iron-blooded. He became a killing machine, his mind turned mechanical, calculative. Everything goes according to his plans and calculations!

In this magical, slaughterous world, a door is opened for him…

- Description from Novelupdates

Kitazawa’s grades at the Ninja Academy had always been mediocre.Uchiha Itachi graduated at seven; he barely scraped through at thirteen.Uzumaki Naruto became the savior of the ninja world at seventeen; at that same age, Kitazawa was still struggling to make Chunin.In this harsh world of shinobi, Kitazawa was what people called a fodder ninja: no talent, no bloodline, and no backing.To stay alive until the story’s grand finale, he’d chosen the safest path—teaching at the Ninja Academy, a job he’d held for five years.“Another peaceful day in Konoha.”Kitazawa rose from his seat and walked to the window.It was enrollment day again, and the training grounds were buzzing with life.He glanced down at the stack of new student files in his hands. Names leapt out at him, all too familiar:Uzumaki Naruto, Uchiha Sasuke, Hyuga Hinata, Ino Yamanaka, Sakura Haruno, Akimichi Choji, Nara Shikamaru, Inuzuka Kiba… and more.'DING''Host has reached age six and successfully enrolled in the Ninja Academy.''Activating the Strongest Shinobi System.'

Humans across the world ended up joining a “Demon Kings and Heroes game”.

Several billion people were set down upon another world to act as “Demon Kings” and “Heroes”. Everyone has to chose their starting races from the start.

Zhang Nu was set in the Demon King camp.

He discovered that he could see hidden information that no one else could.
[Slime Demon King]. Low grade demon king bloodline… Not recommended!
[Kobold Demon King]. Low grade demon king bloodline… Not recommended!
[Dark Elf Demon King]. Mid grade demon king bloodline… Can be selected!
[Bloody Giant Demon King]. High grade demon king bloodline… Recommended!
[Abyssal Dragon Demon King]. Strongest starting bloodline… Extremely recommended!

Should an untalented guy like me die?Then I’m going to die.I will die as you so desire.After dying, I will challenge the world again.Until I kill this tr*sh-like world!