Chaos Heavenly Emperor Technique - Chapter 15 - 0 One Sword!

The notorious firearms crime lord Chen Zhang An a.k.a Old Fox was placed under house arrest by the very successor he groomed.

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 don't share my possessions, Mr. Campbell. Your wife stole from me and now I want something back. You should know I always collect what I'm owed,”When Liam Campbell's wife steals from his wealthy female boss and disappears, he's left to face the music. But his boss, Lady Isabella Ashworth, has other plans for repayment—plans that involve keeping the handsome man for herself.Everyone thinks they know the score: young guy becomes a rich woman's plaything. What they don't know is that Liam's got more weapons than just his looks. Behind his perfect face lies a ruthless mind that turned him from a nobody into a rising star.Now, trapped in Isabella's world of luxury and power, he'll play her game—but by his rules. His main goal is to dominate her as much as she wants to dominate him.But who's really taming who?

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