Building The Ultimate Fantasy - Chapter 620 - If he was so outstanding, he wouldn’t have any friends

In the night, cook wine with the master and discuss the way of heaven and earth!

In the snow, Yu Jian chased the tide of Guangling River!

- Description from novelbuddy

They were born with magic, raised in chaos, and trained in sarcasm.Now the royal kids are all grown up—and the world isn’t ready.Between family feuds, resurrected villains, and a five-year-old firebender with an attitude, the palace is basically a magical daycare with crowns. But when revenge hits home and the kids take charge, things get wild, weird, and a little too flammable.Royal duties? Nah.Sibling wars? Always.Saving the kingdom? Accidental.Welcome to the most dysfunctional, dangerously magical, and absolutely hilarious royal family you’ll ever meet.

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.