MTL - From Becoming the Master of Monsters - Chapter 716 Dire situation, troublesome god

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 price for saving the world is the right to rule it. After saving a faraway land, Lyn Rivers was cast back to Earth. Wanting the admiration, prestige, and glory of saving that realm, she forced her way back. But she was forgotten, and someone else claimed credit for her deeds. Now, with the power of a deity of destruction, she desires nothing more than to claim her place in history. To do that she will conquer dungeons, make alliances, destroy kingdoms, and build an empire. After all, why ruin the world when you can bend it to your will?

I had transmigrated into my favorite game, as an extra who died before the story even began.In a world where Sigils dictate power, I found myself in the body of a boy who had already died on the battlefield.Yet, as I drew breath in his place, his Sigil changed. A power never meant for him, never meant for me.Kidnapped by a shadow organization that didn't exist in the game, I spent three years in the dark, forced to learn under a so-called teacher.I move forward, not as the extra I was meant to be, but as one who chooses their own path. A path to supremacy.Yet the deeper I walk, the more I realize… this world holds secrets that game had never shown.-----------------Additional tags:[Sword Companion], [Hidden Identity], [Artifact Power], [Slow Reveal], [Secret Society], [Survival]

Jiang Bai woke up one day and found with shock that he had transmigrated to a parallel world that is similar to Earth. There, he was granted a cheat system to help him forge the path of a tyrant in this new world. He was now stuck in this parallel world body, the body of a weak and cowardly person. Join Jiang Bai as he rose to the top in this new world!

- Description from Novelupdates