Worldwide Survival: Begins As An Island Owner - Chapter 397 - : The Master of the Mechanical Island Has Been Discovered

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.

I Became Hades, the God of the Underworld from Greek and Roman Mythology

Xiang Yi was most famous vase in the entertainment industry.

It’s said that the prince of virtue had almighty martial arts. It’s said that the prince of virtue had the most handsome appearance in the world. It’s said that the prince of virtue was brilliant. But all was legend! A fire ruined his wonderful appearance and his legs. Even the talented bride under their marriage agreement were replaced furtively. Ye Liu-li was his bad-luck substitutive princess. She went a long way to graduate from Medical University and had her internship with pain and joy. Who knew that in order to save a suicide patient, she fell off the building and crossed time into a “chessman” of prime minister. She had also been married to the disabled prince replacing her elder sister. On the wedding night, when most other couples were having their romantic night, she was thrilled. It didn’t matter. Revenge never came too late. She would never let go of any of them who entrapped her or harmed her.

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