MTL - The A in the Opposite Dorm Always Thinks I’m Pretending to be a B - Chapter 2 2nd

Wake up and an unknown door has appeared in your home… Behind each door is a completely unfamiliar world.In the nightmare world, Jiang Cheng relays the news from the Hunk to the Fatty, adding his own spin to the story.The Fatty almost cried in fear hearing it.“My whole family will be strung upside down for blood-letting if I die here?”“That’s what I heard.”“Then, how come you don’t look scared at all?” The fatty widened his eyes.Jiang Cheng turned around and replied in a very formal tone, “Because I’m an orphan.”

Tian Man Continent is a world of martial arts. A young boy named “Su Yi” led countless yao (monsters or demons) and overrode countless families who had thousands of years of history. He rose abruptly in the world as the brightest star in the sky. He married beauties and walked towards the peak of of the world, and finally ascended onto the thrones of the ancient gods!

- Description from novelupdates

“Even death can't stop me from reaching the top.”Alex clawed his way to the top through sheer hard work and ruthlessness, only to be betrayed by someone within his own group.Although he managed to kill the traitor, he lost his life in the process.But just when Alex thought it was the end, fate had other plans for him.Reincarnated into the world of a novel his girlfriend used to read, he was given a second chance at life.His goal remains the same, but this time, he awakened a mysterious system and surrounded by a harem of alluring beauties.Follow Alex journey through this vast new world as he uncovers the truth behind his reincarnation and the otherworldly goddess who made it all possible.

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.