MTL - Never Marry a Man With Two Tintins - v3 Chapter 13

Once the ultimate Soldier King and a supreme assassin, empowered by a magical Magic Bracelet, had mastered Cultivation, Medical Skill, X-ray vision, and foreseeing the future… became an omnipotent master of pretense. Come, come, come, watch the omnipotent master of pretense teach you a few tricks of pretense.A demonic man who walked out of a major foreign prison, yet married a cold Queen-like CEO wife, leading a life where “you glare at me with displeasure, and I look at you with disdain.”

Coming to my senses... I find myself a desperado.In the depths of azure, black sails flutter.Treasure gleams, blades ring out.Pillage, slaughter, irreverence towards the gods.Youth fades swiftly, all but meat and wine for pleasures.[Slice of Life][Romance Simulation][Business Simulation]

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.

After getting forcefully reincarnated into a world of an otome game he has no clue about, the protagonist is then killed and brought back to life by the prideful villainess with one desire.

To rule the world.

As the ruthless girl’s Eternal Servant, how will he dodge the fate that the game system has in store for him?