There Is No World For ■■ - Chapter 141: Side Story - The Case of the Princess

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.

How could a poor graduate student without any background or connections become successful? With a coaching system? An upgrade? This is not a computer game, but real life we’re talking about!

After playing a variation of the poker game, Shadow’s Hand, Damien Pearce unexpectedly awakened in an unfamiliar world.Stripped of all kinds of information in the world he was thrown into, Damien now had to navigate it through wits and guts.Amidst his search for information, he discovered that he seemed to be a part of the world as a Transcendent Investigator, otherwise known as TI.The TI seemed fearful and revered among the people in this world. They were responsible for catching Transcendent(s) who misused their power.But was that the reason for his transfer?“Do I or do I not belong in this world?” Damien questioned his presence constantly.

With the memory of a Level 200, Tier 3 Mage. Lu Yang returned back to his life ten years ago. Destiny made a joke with him. He was betrayed and everything he worked for was taken away. He had to get it back.

The game’s money making methods, dungeon strategy, legendary quest, equipment source, secret blueprints, combat skills. He knows all. See how a reborn player with his brothers swept the country, burned the world and created the legend of The Fire God!

- Description from Novelupdates