My Toxic Ex-Wife: BOSS, Stay Away！ - Chapter 112 I Am Willing to Wait for You

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.

Thrown into a brutal world of swords and sorcery, his memories stolen by an unseen force, Magnus wanted only one thing: to go home.But every kingdom, devil, and god — along with regressors, possessors, and fellow reincarnators — seeks to carve him apart.Survival demands war. War demands survival.And with a System that hides more than it reveals, Magnus is dragged down a bloodstained path... one battle, one betrayal, one broken world at a time.

Once, because of a pair of purple eyes he was scorned. He is a wangye known across the land, cold and bloodthirsty, looking disdainfully upon the world.

Once, because of a mother’s death she received a father’s resentment. She is a publicly known junzhu whose looks have been destroyed, pitiful and weak.

In reality, he has a pair of this world’s most beautiful eyes, the most formidable background, the most imposing strength.

In reality, she has a peerless face, the most unshakable background, and the most ingenious medical skills.

She, Lan You Nian, aloof and cold-hearted, underneath the appearance of a celestial maiden is a battered, wounded heart.

When the cruel and ruthless him met the indifferent her, who adores who most deeply? Who once again puts a smiles on for whom?

- Description from novelupdates

In a world where the strong prey on the weak and nobles slaughter commoners like insects, Alex was just a weak boy who lost everything to the cruelty of fate.For the sake of revenge, he rose from the ashes, determined to carve his path through a world soaked in blood and betrayal.But there is something the world does not know—something even Alex himself has yet to discover...A power buried deep within his blood, ancient and untamed, waiting to awaken.