A Cliché Multiverse Story - Chapter 14 - CH. 14: Saya Takagi (Part 1)

The Spirit Blade Sect was founded in the year 4233. After thousands of years of producing first rate Xiuxian geniuses, it had become one of the five biggest sects in the Ten Thousand Celestial Alliance. The head elder, Immortal Feng Yin is one of the seven Executive Elders of the Ten Thousand Celestial Alliance, with a cultivation that can shake the whole world. The Spirit Blade Sect is dedicated to peaceful development, and holds the core values of Truthfulness, Kindness and Loyalty. In order to expand the sect and bring in new blood, all heroes and geniuses have been welcomed to attend the Celestial Gathering.

Humanity was on the brink of destruction. Muyoung, an assassin from the Forest of Death, fell to his knees. There were corpses all around him. For years, he had worked for the Forest of Death and had finally been able to eradicate them. Now, he, himself, was about to die. He closed his eyes as he felt his heart stop beating.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

In Academy City, magic and science coexist in an unwavering power struggle. Toma Kamijo, an academically-challenged student in Academy City, wields the power of the Imagine Breaker in his right hand, which allows him to completely negate all supernatural powers – as well as his own luck. When he happens upon a mysterious nun named Index, whose mind has been implanted with the Index Librorum Prohibitorum – 103,000 ancient texts banned by the Church – Toma’s luck is about to be pushed to its limits when he finds himself in the middle of a war he never expected!