Reborn In The Apocalypse: It Had Always Been You - Chapter 14

She was stupidly in love with him. Because of him, she became rude and unreasonable, overbearing, jealous, insane. But he did not spare a glance to her. Married for two years, he didn’t favor her once, letting her become the laughing stock of the whole world. Eventually, she ended up in an affair, leading to her tragic death.

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.

Pain, Pain, Go Away is a novel by Sugaru Miaki, also known as Fafoo, author of Starting Over and Three Days of Happiness. Unlike Miaki’s previous two books, Pain, Pain, Go Away is not a rewrite of any story posted to 2ch, but an entirely original one.

The plot involves a young man who becomes a killer (by accident) – but his victim has the power of “postponement,” temporarily delaying her death.

Jiulong Continent, ancient times had Nine Dragons!It is said that one who obtains a dragon can stand above billions of people; one who obtains nine dragons shall become the ruler of the continent!Young Yun Xiao, in an attempt to save a treacherous individual, suffers severe injuries to his meridians. However, he experiences an extraordinary twist of fate and rises from dire circumstances. He merges with the soul of the Dragon Sky War God and is reborn, thus beginning his own legendary tale of defying destiny.“Eh? Isn't this a parasitic wasp?”“Who says it is a parasitic wasp? Have you ever seen a golden parasitic wasp?”“Even if it is golden, it's still a parasitic wasp!”“No, it is a dragon!!!”