I Contracted All Ancient Divine Artifacts - Chapter 8: Assessment Over? No, It’s Just Beginning

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.

A world where waves of monsters descend every night...A world where only the strong can survive.Axel, a burned-out man from modern Earth, wakes up in a desolate wasteland with nothing but a strange “Harem Settlement System” with him.Given the power to build, command, and grow stronger, he sets off to carve out a safe haven in this broken world. But as his settlement grows, so does the number of beautiful and deadly women drawn under his blanket-ahem!-banner.Witness Axel's journey, rising to to the peak. From a simple, lone survivor to becoming the Wasteland Overlord. With the help of the loyal, dangerous, and irresistible thirsty harem girls!

She is a top-class spy, a poison specialist, but also a young and cute girl with a sinister temperament. In spite of her sweet and innocent appearance, she can complete any tasks without the slightest hesitation. One day because of an incomplete black magic, she was sent into the body of a girl who was deemed as a good-for-nothing. What kind of change will she bring to this continent?

A Prince said with bitter hatred, “I thought she was weak and easily bullied, therefore I broke off the engagement. I really didn’t expect she is such a shrewd girl. I made an error of judgment.”

The Crown Prince deeply sighed, “She is such a sexy evildoer! Obviously, she has a frail and tender body, but I am not able to overwhelm her…”

Finally, an Emperor hit the nail on the head, “She is just a bit two-faced!”

She answered, “You’re just a big pervert!”

The Emperor carried her into the room and said, “You are predestined to be mine! A two-faced girl and a pervert are a perfect match, right?!”

- Description from Novelupdates

[Mature Content.]**[COMPLETED.]**Winter’s second marriage was nothing like the fairytale of her first. She spent the past two years being intimidated and abused by her evil mother-in-law, Camilla.She endured it all for the sake of her second husband, Sebastian. But she was finally pushed to her breaking point when she found out that Sebastian cheated on her and seized all of her assets accumulated from her previous marriage.Winter was left with nothing but a baby in her womb.“You have taken everything from me, Sebastian Saenz. So I will take this baby with me to the grave. He doesn’t deserve to be born unloved by his scum father,” Winter said before she jumped from the balcony and plunged to her death.She thought she’d end up in the afterlife with her first late husband.But she found herself back in the past, two years earlier when she had just finished her wedding reception with Sebastian Saenz.Thus, equipped with the knowledge of her misfortune that would happen two years from now on, she vowed to protect herself and everything that her first husband left for her from the hands of her greedy second husband and mother-in-law.But what would happen if Sebastian also returned back in time to beg for her forgiveness.Would she give him a second chance?Or would she destroy him just like how he destroyed her in their previous life?“What should I do so you will forgive me, Winter?” Sebastian asked as he was on his knees. “You are the only one I have, so please…”Winter stood coldly, staring down at the man who ruined her in the previous life, “Then I will take everything from you, Sebastian. I want you to know the anguish I felt in my last moment.”