One Planet for Everyone! Building Science and Technology Civilization at the Beginning - Chapter 12: Jurassic! The Age of Dinosaurs?

Ukei Kaito fought a desperate struggle in order to fulfill his role as a summoned hero. He defeated the Demon Lord and saved the very world, only to meet an end filled but with betrayal. The companions that he’d trusted throughout his journey betrayed him and killed him by sticking a blade through his chest.

The Overlord, Kang Chul-In. The man who was so strong that he had to be defeated. Having lost, he must now go back in time to take up the challenge of becoming The Emperor in the Continent of Pangaea. Will Kang Chul-In be able to overcome the 9 other Overlords in order to grasp the Continent of Pangaea within his hands?

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…

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Let’s fight! Go! Who am I afraid of with a chip that turns into a brain cell? ! Get promoted and get rich! The nest treasures are all mine!

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