I Became A Hit After My Divorce! - Chapter 806 - : Glass Imperial Jade

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.

Within the Huang Realm, a world where the era of divinities has ended and the era of immortals is nearing its waning years, exists the Buzhou Immortal Sect. And within the Buzhou Immortal Sect on Jade Peak was a disciple of the sect, Xi Tianyi. He was of noble birth, the only child of the Sword Empress who reigned invincible.

But the truth was that Xi Tianyi, was originally an ordinary mortal from Earth who suddenly woke up one day as in another world filled with immortals and demons. Under heavy pressure, knowing that his life is at stake to whoever is strongest, Xi Tianyi quietly cultivates in hopes of one day fearing no one and discovering the circumstances of his transmigration. But…

«You bastard, you stole my fiance!» Said a former genius who had lost all his cultivation.

«Bastard, pay with your life for the death of my entire clan!» Said a cultivator with blood leaking from his hatred filled eyes.

«What the hell?! I’ve been cooped up cultivating quietly so why are you guys suddenly finding trouble with me?! Besides, I’m only ten!» Cried out Tianyi in disbelief.

«Fine, if you want to make me your cannon fodder, I’ll step on your corpses for my ascension!»

[Cover] NOW HIRING — URGENT — Ghost Story Specialist Corporation Daydream Inc. (Ltd.) Insane Benefits – Come to Work Immediately ※ Note : The company is not liable for any injuries or fatalities that may occur during the course of the employee’s duties. —— A pop-up event for some ‘modern fantasy’ media I loved so much that I even took a precious day off work to attend. On that day, I ended up transmigrating as a character in that very fantasy world. As none other than a newly hired employee at a famous large corporation! A dream job with great benefits, an excellent salary, and even kind and competent bosses. I’m using the information I know about the world to rise through the ranks at lightning speed! Am I happy, you ask? Please, just let me go home. I’m begging you. ※ Note : The genre is horror.

One day, I was given the mysterious power of Hwanmong.