One Piece: The Soul Purchasing Pirate - Chapter 136

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.

When Simon dies, it turns out there's more to combat than lightning reflexes with his controller, and the path to becoming a hero is more brutal than he can imagine as he descends into The Pit. Death after Death is a dark, time loop/Isesaki story with roguelike elements, that explores some of the common tropes in a different light.

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

Ren thought getting sacrificed and becoming a holy spirit was rock bottom—until he discovered his divine wife, the Goddess of Magic, is completely broke on faith power. That means his remaining soul would completely disappear.Turns out magicians are the worst believers ever!Ren has a crazy idea: if magicians won't pray willingly, make them pray to access the internet.Starting with a simple magic forum, Ren introduces this fantasy world to the addictive power of online connectivity. Want Q&A sessions on spell theory? Pray first. Need to livestream your dragon research? That'll be one prayer, please. E-commerce shopping for rare magical components? Prayer required for checkout.The moment Ren becomes the God of Technology, this world's whole vibe goes haywire.What begins as a desperate faith-farming scheme spirals into something far bigger. Soon dragons are running delivery services, apprentices are binge-watching magical tutorials, and even gods are competing for subscriber counts. Magic cars cruise the streets, magic trains thunder across continents, and when apprentices start wielding magic ray guns against seasoned magicians, everyone realizes this world has changed forever.From a simple forum to consciousness uploading and biological immortality—when technology crashes into magic, the explosion reshapes reality itself.After all, why choose between science and magic when you can have both?