The Great Demon System - Chapter 16: Your What!?

The dust thrown into the atmosphere by the impact obscured the sky and plunged the world into an Ice Age that would last for hundreds of years without sunlight.Because of the lack of sunlight, Earth's surface had fallen to extreme cold temperatures down to tens of degrees below zero.Facing impending doom, Chen Xin was left with a shelter that he built underground and an upgrade system he found. How would he survive the crisis?Could human civilization prevail? Would the embers of hope be enough to illuminate the cold night and bring warmth to mankind?Destiny had brought forward a harsh trial. Could human beings avoid sharing the same fate as those of the dinosaurs that were extinct?

What would happen when someone from our world was suddenly reborn into the world of My Hero Academia with a Gacha System that rewards him with abilities, techniques, and skills from Jujutsu Kaisen? Grand epic fights and crazy shenanigans as he goes through the story to cause chaos and change the world to his liking.

Reborn as Red Army Misha!

- Description from novelbuddy

I got transmigrated into a game I’ve never seen before.

I thought it was a top-notch RPG and spent 30 years on it.

I retired as a war hero and planned to spend my remaining time leisurely.

But it turns out, it was an academy story?