Legendary Armament Canon - Chapter 264 - : The Owner of the Heavenly Halberd, Money Falling From the Sky (1)

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.

In the northern part of the world, a long-standing battle between various races and the demon race has finally reached its end. The Demon Lord, a figure with black hair, red eyes, rules from her obsidian palace, having repeatedly defeated the Goddess, the strongest being in the world. However, she refrains from killing her, knowing she will only be reborn to lead another attack.As the goddess kneels before her, badly injured and helpless, the sounds of explosions echo outside, signaling the imminent victory of the alliance. Despite her immense power, the demon lord acknowledges the demon's overall weakness compared to humans and the Alliance. The development of fighting energy and mana has allowed ordinary humans to fight demons, leading to the demon army's defeat.Aware of the Alliance's intent to enslave the abyssal demon, the Demon Lord decides to cast a forbidden spell that will cost her life. As the Alliance forces storm the palace, they hesitate upon sensing the spell's energy. The Demon Lord vows to resist and be reborn to save her people.Meanwhile, the goddess reflects on the demon lord's past treatment of her and acknowledges her respect and dedication to her people. As the demon lord prepares to cast the spell, the goddess asks if she can abandon her plan and live freely. However, demon lords are duty-bound to restore the demon race's glory and protect her people.Understanding the demon lord's resolve, the goddess readies her sword, intending to clash with the demo lord's forbidden spell. The resulting explosion creates a mushroom cloud, marking the end of the conflict and the start of a new era. The Demon Lord and the Goddess become historical figures, their stories occasionally told.

A man betrayed by a comrade dies a wretched death as a third rate swordsman. His existence, his life, his emotions are all a nuisance in the eyes of society. But wait… What’s this green skin? Reincarnated as a goblin? Wait, I went back in time as well?

Nate, a transmigrator from Earth, arrived in the anime world of Fairy Tail!He acquired a magic called “Internet!” He developed it and got everyone hooked!You can livestream, chat, and even... hmm? Find girls to date!Sasuga Nate-san, Internet Magic is the best!