Tenkomori: The Homecoming Club Conquers Another World - Chapter 100.2 - The Second Year at the Academy - [Create Magical Tool]

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

Sequel of Allison, taking place about 17 years after the original series.

In an era when the power of Fire Magic was considered to have reached its limit, one girl began researching nuclear fusion.