I can return to the age of mysterious - Chapter 1178 - 593 The Unification of the Three Great Personalities, Ultimate Origin (4400)

Shen Gu, an ordinary university student who discovers that he is a “spare tire” in his social circle.With the help of a system, he gradually rises to the top of life!

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.

​The world, Earth, was devastated by the Great Incursion, an apocalyptic invasion by dimension-hopping monsters. Humanity's only hope now lies in Galaxy Fall, a newly accessible parallel world where they can gain strength through a System of quests and missions.​Five hours after the Invasion, the betrayed survivor Mirabella is mysteriously reborn and gains a unique power: the [Master Account System].Her initial skill is the deceptively simple but devastating 'Multiplier x100', which applies a 100 times buff to all her offensive capabilities, including physical attacks, spirit energy skills, and damage-over-time effects.​Mirabella must now transform from a silent survivor into the world's most feared warrior, who was only scared of one thing, which is?“I Hope I don't run out of opponents in Both worlds.”

He is high above, the mysterious and terrible King of the Wild. With one glance, he can see people’s romances. He hates women to the extreme, but at his first glance of her, he dotes on her and spoils her.
She is a humble transmigrator, a miracle doctor who doesn’t care for the many handsome men around her. She only wants to become strong, to be worthy of that god-like man. But when she’s finally sure of her feelings, she finds out she’s already been married for years…
……
When wronged：
She uses strength to hit the big handsome iceberg-like man in front of her eyes. “People say that I’m not good enough for you, but it is you who is an old cow eating tender grass!”
A man seizes the main point and laughs like an evildoer. “This husband has to eat the grass to confirm if it is tender or not!” He puts out the red candle……
……
The world says：
The barbarian king has no heart and has no passion.
A pregnant woman very miserably thinks,” If he has no passion, then who is responsible for this big belly?”

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