I Was a Sword When I Reincarnated (WN) - Chapter 605

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.

“I am the rot in your foundation. I will crawl back from hell and bury this world.”Those were Red’s final words as his classmates—the people he once sought validation from—watched him dissolve. They stole his life force to fuel their own ascensions, becoming Paladins, Sages, and Kings. They threw his empty husk into the Abyss, satisfied the 'Terrorist's Son' was finally gone.But death was not the end. While his body lay broken in the abyss, his soul drifted to the sanctuary of a Forgotten God.Awakening the forbidden SSS-Rank Talent [Exponential Divinity - 100x Growth], Red realizes that in this world, power isn't given—it's built. He doesn't need heroes; he needs monsters.From the chitin of hyper-evolved insects to dragons, from eldritch horrors to the nightmares sleeping in the dark, he begins to construct a civilization that defies the natural order. Under his hand, the weak do not just survive—they evolve into calamities.The Heroes are leveling up in their golden towers. The Gods are watching from their thrones.But in the shadows, Red’s Strongest Civilization is already preparing for war.[Betrayed and sacrificed, I awakened an SSS-Rank Talent. While others struggle to build a village, my civilization grows 100x faster.]

Liu Ergou grew up in the village and studied medical skills with his grandfather. After his grandfather died, the responsibility of treating the villagers falls on him. But an accident bestows upon him an inheritance from his great-grandfather, which sets him on the path to invincibility!

To save her family, she got married and divorced not for her own will. Due to the “derailment”, she was left penniless by a divorce settlement. She finally knew it was Di Juehao, her handsome, indifferent and rascally husband of the rich family, who plotted everything! However, she gave him an impolite impact on The day they divorced! Five years later, Wen Nuan made a good showing and became Top 1 designer of a world’s famous brand. She returned with two kids. Unexpectedly, she was forcibly taken by her ex-husband Di Juehao to the hotel to have s*x as soon as she returned. In the end, Wen Nuan gave him 10 yuan and left with pride: “Hey, 9.9 yuan is the market price for a top 1 male prostitute now. The rest is the tip for you!” But when she rushed to the company, she was surprised to find that his boss was…

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