The Steward Demonic Emperor - Chapter 1258: Deal

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.

In his past life, Ethan Steele was an ordinary man living in a modern world—working a dead-end job, struggling through the monotony of daily life, and haunted by regrets of missed opportunities.At the age of 23, his life came to a sudden, unexpected end in a car accident. As his consciousness faded into darkness, he was sure it was over.But fate had other plans. In the divine realm, the God of Fate watched over the balance of life and death.Ethan's untimely death was a mistake, an anomaly that diverged from the preordained path of his destiny. It wasn't yet his time to die, and so, the god decided to give him another chance.“You were meant for greater things, Ethan Steele,” the god's voice boomed. “To correct this error, I will reincarnate you in another world—one filled with magic, swords, kingdoms, and adventure. You shall be reborn, but you will not remember your past until the appointed time. There is, however, a... complication.”By divine error, the god accidentally bestowed Ethan with the Harem God System without having any idea about it.This system is a powerful, reality-bending system that would allow him to charm and seduce influential women to build his harem, growing in strength and power with each conquest.“Your memories of Earth will return on your seventh birthday. I hope you enjoy your life here in this world”And with that, Ethan's soul was transported to a new world.

The mighty heavens exist, ruling over all things. Those favored by its will are granted power and fortune, while those who dared to oppose it perished, leaving none behind. This is the tale of a man who once defied the heavens, underwent multiple reincarnations, and returned once more to the cultivation world. But here’s the twist. This young man remembers nothing of his past lives and is simply a teenager from Earth. How will he who has no knowledge of cultivation and experience in fighting, survive this grim world while being an inner disciple of a lower realm force—or so Xiao chen, the teenager thought till he heard a systematic sound in his mind. [Ding! Host has awakened the heaven’s destined villain system!]

A regular senior high school student accidentally obtained a Supernatural Ability System from three thousand years in the future. Lin Tian could exchange for all kinds of superpowers within the Supernatural Ability System. Exams? I have a photographic memory! You’re amazing? I transform into a Saiyan! An awesome life doesn’t need explanations!