Elf Tensei Kara no Cheat Kenkoku-ki - Chapter 13Book 3: -2: Where Did I Go Wrong?

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.

The era of the decline and fall of the galaxy has arrived, and the power to destroy the world has gathered unprecedentedly.

The minions of the four evil gods are wreaking havoc in the real universe. The terrifying monsters and demon legions in the dark night of old have brought destruction and despair to countless human worlds.

In the darkness, a ray of light emerged.

Carrying countless human technologies, the soul from another world came back to life with the help of the body of the thirteenth parent and child of the imperial emperor.

The battle between humans and evil gods is rekindled.

In the name of the Emperor, countless human heroes gather again.

Blood and corpses will pave the way for the glory of mankind.

“As soon as I opened my eyes, you told me that human beings are about to die??”

- Description from novelbuddy

Neo was on the verge of achieving his dreams, set to graduate with flying colors and secure a bright future. But fate had other plans.One moment, he was lounging in his apartment, enjoying his simple and ordinary day. The next, he found himself in a nightmare—a brutal game orchestrated by the hidden rulers of the world.But Neo wasn’t just another victim. When he was pushed to the brink of death, something awoke within him—an ability unlike any other. God-Tier Adaptive System .Every injury made him tougher. Every battle made him smarter. Every encounter shaped him into the perfect survivor.Now, he isn’t just fighting to escape. He’s evolving. And soon, those who once saw him as prey will learn to fear him.'To kill those sick monsters, I must become something far worse.'

I was possessed by the game (forced).