Invincible - Chapter 3751: The Devil Mirror Palace Appears

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 regards to the MMORPG Cross Reverie, Sakamoto Takuma boasted an overwhelming strength that was enough for him to be called the Demon King by the other players. One day, he gets summoned to another world with his appearance in the game. There, there are two people that insist “I am the real summon master.” Takuma gets slave-turning magic used for summoned beasts cast on him by the girls –

Chi Yiyin is regarded as a top horror novelist, and everyone who has read his books said it was like being followed by fear itself.
What they didn’t know was that it was Chi Yiyin’s personal experience.

While exploring a haunted house at night to find inspiration, Chi Yiyin was dragged into another world.
It’s a crazy and dangerous world, full of ghosts and fallen god. Even if human beings awakened their blood, they could still only survive in insignificant ways, and if they made one wrong step, they will usher in tragic death.

However, when the other players were scared to death and could barely survive, Chi Yiyin took out his small notebook: “This is truly terrifying, it can be used as inspiration.”

The ghost froze: ? Please respect me, thank you.

The next moment, the ghost was sealed into Chi Yiyin’s notebook and became his tool ghost. The ghost was dumbfounded.

All ghosts that were successfully written into words by Chi Yiyin will be sealed in his book for his use.

In the game world, rumor about a human began to circulate——
Chi Yiyin is here! Scared me to death, run!

The fallen god sits on top of the game world, full of loathing.

However, He saw the dazzling starlight, traversing the world against all odds, and came to Him.

He loves me.
The fallen god thought to himself.

Then this world that should have been destroyed has meaning to continue existing – for him, the sun rises.

“Don’t write about those crooks, I can be your strength. Fill your book with my name, and you will become a new god, and I, your most faithful believer.”

The fallen god kissed deeply: “I will give you a god, full of devotion and belief.”

People who were eagerly waiting for Chi Yiyin’s new book discovered, the top horror novelist actually wrote a love story??

Chi Yiyin announced with a smile: “Yes, I’m in love.”

“With a god.”

- Description from Novelupdates

Have you ever read a story? So stupid and senseless that it makes your blood boil and makes you pity even the villain of the novel. if you haven't that's fine because our protagonist did.“FROM WHERE THE FUCK DID NTR COME FROM?”He threw his console controller on the which did a cartoonish bounce and formed a bump on his forehead.------“Wait! What's this place!?”The moment he woke he found himself in a strange location never been visited by him ever before.------“No!! No!! No!! How the hell did I end in the body of this cucked villain! Why did I end up in this body!!”He lamented when looked at his face in the mirror that got beaten blue by the protagonist of the game.------“Don't worry, Riech. I will fulfill your and fucking kill the bastard and fuck his mother and avenge you!”He clenched his fist and gritted his teeth in anger vowing to take revenge.