I Met The Male Lead In Prison - Chapter 213.2

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.

One day, a silver-haired goddess appeared before him.“Heaven-Defying Star. The one who goes against fate. The sole savior of a world doomed to end—”What the hell is this woman even talking about?“You must be the Regressor.”“… What?”No, I’m not.

After waking up in the body of the Young Master of the Luo family, he finds he has the knowledge of hundreds of games and Light Novels. However, he finds his Dantian is crippled, so he can’t practice cultivation! Luckily, he has the Upgrade system.

Killing Monsters, doing Quests, and even killing people- it’s just too easy. I don’t have any Martial Arts? I have hundreds of light novels, just let me level up so I can get this Main Character’s Martial Art! The only problem is: Should I follow the “This OP character cultivation” or should I follow “Another OP character cultivation”?! The tragedy!

- Description from Novelupdates