Close Combat Mage - Chapter 457

A side story series featuring the girls of Kyoukai Senjou no Horizon.

When Arran decides to become a mage, he quickly discovers that magic can be more dangerous than he had ever imagined. Soon, he finds himself hunted for powers he never knew he had.

With the unexpectedly obtained unknown civilization technology, bionic robots, artificial intelligence, quantum mechanical transmission, supercomputers, plasma thrusters, nuclear fusion, these black technologies are constantly being manufactured in Wang Xiao’s hands.

Knowledge is power. With the help of unknown civilization technology, Wang Xiao, who has acquired this knowledge and black technology, has tickets to a better future and a sea of stars.

- Description from Qidian

Roy died during a war against the Evil God Cult, but somehow, he returned back in time to 30 years in the past where he was just a boy who awaken his summoning magic.