The Legendary Hero is an Academy Honor Student - Chapter 25: The Forge of Heroes

The world has ended. I’m the only survivor left in the shelter. But by my side is the world’s most advanced AI, Artemis.

Time travelling from the majestic era after the Recuperation of Reiki, he became Kimura Kazuki, a 16-year-old high school student in Japan, one year before the Reiki Recuperation.

Tentatively, he set out to hone himself to the bone, burning candles at both ends to stockpile resources in preparation for the imminent Recuperation of Reiki. His goal was to be many steps ahead of all humanity when the time comes.

However, it seemed like fate had decided to play a cruel trick on him.

One year later, the Recuperation of Reiki… did not happen as expected.

- Description from Novelupdates

In the blood-soaked world of Magus , Aizen, a young man from Earth, finds himself thrust into a brutal reality where Sorcery reigns supreme. Once a lowly servant, despised and humiliated, Aizen hid his true intentions beneath a mask of submission. With each insult endured and every drop of blood spilled, he sharpened his resolve, guided by the mysterious Wisdom System.

After the nuclear warfare, massacres started to spread throughout the entire world. The order between humans completely collapses, and the strong eats while the weak gets eaten becomes the #1 rule.