The Ice Lord Prime Minister's Black-Bellied Wife - Chapter 1

The most unexpected weird destiny,
The most intense brain collision,
The cruelest battle of life and death,
The craziest bizarre fantasy,
The most bizarre truth …
It’s the first time, and another ten years!

- Description from Qidian

The Story of One Continent ~Allison and Wil and Lillia and Treize and Meg and Seron and Everyone Else~ is one final send-off for the long-running series of novels by Keiichi Sigsawa that includes Allison, Lillia and Treize, and Meg and Seron.

As this is a sequel that involves characters from all three series, you are advised to read all of Allison, Lillia and Treize, and Meg and Seron before diving in.

Life is unpredictable. Her husband loved her stepsister, deposed her as Empress and even forced her son to death. In that Cold Palace, she was forced to drink poisonous wine. So in the next lifetime, she made a promise to never do good deeds and help others, to never step into the palace and to never become the Empress!

At the Prime Minister’s estate, the mistress’ daughter is reborn into a she-devil.

An evil stepmother? I will make sure you go to Hell!

A two-faced, hypocritical older stepsister? I will rip apart that beautiful façade!

A scheming younger stepsister? I will throw you into the grave!

You guys didn’t let me live peacefully so you should also expect the same!

Initially she wanted to stay away from disaster as far as possible; however, a man’s heart is like a needle in the sea—impossible to search for, impossible to understand.

The man who once swore to abandon her became someone who can’t live without her.

The enemy from the past lifetime suddenly confesses his feelings for her.

Even worse, she is bothered by a handsome man with a thick-skin who doesn’t know how to give up!

- Description from Novelupdates

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.