Stunning Poisonous Doctor Princess - Chapter 919 - The Banquet for the Emperor

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.

The ending of fairy tales is usually a happy ending of the hero and heroine. As for the supporting characters, who will care about their happiness? Having such a bad thought one day, they suddenly turn dark. They want to revolt, and they don’t want to be the main couple’s stepping stone for their ‘True love’ again. Oh my god! What’s about the plot? What kind of story will it play out with a character like this? Can it still run smoothly? The hero and the heroine are going to be crippled by the supporting character!!!!! Well, there’s actually a project to save the plot from it. By nipping the bud of all evil thoughts from them, and let the hero and heroine live together in happiness. The named of this project is ‘To save the supporting character’. All executors must dutifully do their work, and as for the mean to achieve it? Oh! That’s not worth mentioning~

No matter whether it is a white cat or black cat, if that cat can catch a mouse then it is a good cat.

- Description from Novelupdates

Arsene Academy – the best educational institution on the continent.

A place that’s famous for nurturing many talented people.

A warrior from a barbarian tribe enters the academy.

An anime otaku who has traveled to the world of full-time hunters, in order to live well, he can only keep getting stronger all the time, burying the strong one after another. Your withered life will be continued by me.

- Description from novelbuddy