Mercenary's War - Chapter 1340 - 1323: First Contact

The dark BOSS, who had the fortune of becoming Earth’s last living human, brought with him his loyal, second last human to die, little brother to be reborn.

What does he want to do after being reborn? Is it world domination or world annihilation?

BOSS expressed, he was completely uninterested in these kinds of things, he only wants to die.

In order for him to make his boss who always seeks death to continue living, little brother is completely unscrupulous, serving his boss to make him comfortable and cozy, then later helplessly discovered…. The BOSS’s behaviour is more and more abnormal!

- Description from chrysanthemumgarden

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.

Akira Kisaragi traverses into the Bleach world, unlocking a check-in system.He initially thought that by checking in daily, he could become stronger, soon become the Captain-Commander, join Division Zero, punch Yhwach, kick the Soul King, and marry Unohana...However, the system's style wasn't quite what he had imagined.〈 Check-in complete, obtained Genryūsai Yamamoto's secret roasted sweet potato! 〉〈 Check-in complete, obtained exclusive attribute: King of Normal Attacks, effect... 〉〈 Check-in complete, obtained Retsu Unohana's... 〉Akira's eyes suddenly lit up!“Seems like this might not be so bad after all!”

In a world where mysticism and steam industry coexist, cursed objects, the Reception Bureau, and Evil God fanatics...That year, the King was bedridden with illness, the successor was inexperienced, and power slipped away, leaving the empire teetering.That year, external forces gathered around the empire, and foreign civilizations eyed it covetously.That year, the prophet delivered a prophecy that the era of civilization was nearing its end.That year, Ethan arrived at a small town on the outskirts of the imperial capital. To survive in this perilous era, he began practicing Fireball Skill.Years later, Ethan looked at the meteor falling from the clouds and realized there was a problem.The beginner Magic he learned seemed a bit off.