Invincible Uncle-Grandmaster - Chapter 386 - Asura Arena?

A surgeon accidentally got the blessings of a system, shocked the medical industry, and rejuvenated countless people.

- Description from Novelupdates

“On that day, Zach Harper died-” Or at least that was how it was supposed to be. I died. But there was good news, and bad news. The good news; I was reincarnated! Transmigrated into the World of Aethoria! Holy fuck, miracles do happen! But the bad news was, “Huh? What’s this?” ... [DING!] A New Quest has been issued:- Type:- SURVIVAL Name:- Quest To Becoming Stronger: Description: The {Great Calamity} is coming...Get stronger and survive. Duration-: ... Reward:- ... Penalty:- Death, ??? ] ... I had to survive.

What if an alien baby born in the midst of a major conflict on another planet was sent to Earth to save his life? Born with intelligence and the ability to create technology from any material he touches, he was found by a couple in rural Japan and raised like a normal human.Despite his powers beyond reason, living in a peaceful world forced him to restrain himself. He grew up as a young man who loved high-tech superheroes, but never had the chance to realize his dream of becoming a hero.However, everything changed when he and his classmates were suddenly transported to another world—a world of monsters, war, and chaos. Seeing the helplessness of the humans in that world, he realized that this was the chance he had been waiting for.Not with magic, swords, or ordinary physical strength—he would become a hero with technological sophistication that surpassed any civilization!This will be Ren Takamura's story!

Fear breaks the boundaries between dreams and reality, and it is impossible to tell which is reality and which is illusory. When the nightmare really comes, no one can be alone.

This is both a danger and an opportunity.

- Description from novelbuddy