Comrade: Almost a Cat-astrophic Love Story - Chapter 128 - Pei Zhen… My Future Boyfriend

Freshly turned eighteen, John Newman, a helpless nerd, suddenly gets video game abilities granted to him. A mysterious higher power, a secret Abyss of magic beneath the surface of the normal world, mages, martial artists, eroticism, tragedy and a harem of hot girls awaits.

God: I shall bestow the Saintess upon you.
Pope: W- wait a moment! This is a boy!
God: That is the Saintess.
Pope: ??????

And just like that, the Saintess was raised by the church for fifteen years without any questions asked…

- Description from Novelupdates

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.

“For those who dare call themselves gods, I, Wen Ran, will crush their legacy beneath my feet. Even dogs are more honorable than those filthy bastards!”A feared Godslayer, who, due to betrayal, perished under the might of the heavens, having his world destroyed. Saved by a mysterious system, Wen Ran was granted a second chance at life but reincarnated in the body of a lowly slave. Hunted by the gods who sought his head, Wen Ran vowed to reclaim his title by showing heaven his vengeance as a 'God Slayer.'