Extra Demon: Sacred Academy of Light - Chapter 172: One for many

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 interview begins:“Boss Gu, what is your view on pursuing women?”“The most important thing is loyalty and protection.”The man turned his head to look at the petite woman beside him, his deep-set eyes glowing with utmost affection.“He's obviously cunning and shameless, relentlessly dealing with both friends and in-laws, without any limits...”Shang Xixia's smile was brilliant, but her slightly twitching lips betrayed her silent complaints.“Boss Gu, why did you choose to inherit and manage the Gu Group?”“There are many ways to live life, I want to...”Gu Jingchen's lips curved slightly, exuding a calm elegance.“If I couldn't be at home all the time,”Continuing her inner complaints, Shang Xixia glanced with great grievance at the man beside her....The most beautiful love is when, after growing up, you are still my beloved childhood sweetheart.

In the virtual world, power is what you seek. In reality, it’s the pursuit of truth.

But the game is not actually a game.

Evolution!

- Description from Novelupdates

For the once dead Hua Yu Man, she has to do three things this lifetime: kill those who harmed her, kill the man who said he loved her, and protect a place called “home.”

She seems docile and gentle, with the air and temperament of a beautiful young lady. But in fact her heart is cold, overbearing, and black belly, with a mysterious identity that can drive the world crazy.

He is the Thirteenth Prince, but also the country’s disgrace; a cold and ruthless man who doesn’t put human lives in his eyes. But only towards a sometimes gentle, sometimes willful and sometimes disobedient woman, would this man be ceaselessly doting and spoiling.

- Description from Novelupdates