This Witch Transmigrated into the Romantic Novel's Supporting Role - Chapter 227: Classmate Gathering

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.

The Queen of the elves wants to bear his child, the vatican’s saintess is his maid and the empire’s princess wants to elope with him.

But his only concern was his delusion of taking down the creator of the world!

- Description from Novelupdates

He was the hunting hound of the Baskerville family.

But at the end, he was branded as a traitor and executed.

— — —

Now, he has returned… after 40 years.

“This time, they will be my prey… and I’ll bite every single one of them to death!”

Vincent Strider was a gun for hire who made a living by killing whoever it was his clients wanted dead. But during one mission, he died in a fierce gunfight. However, death was not the end for him. Vincent found himself reincarnated in another world, facing a floating interface that flickered before his eyes.[Synchronizing Host!][Military System initializing.]Vincent found out that in this system he received, he can summon soldiers, tanks, aircrafts, and even warships! This is going to be exhilarating.