Girl, I'll Teach You Cultivation - Chapter 275

The Special Investigations Unit is a covert organisation that no-one in the city knows about, dedicated to investigating bizarre occurrences beyond the comprehension of the living. The Chief Zhao Yunlan isn’t a simple guy either, being the inheritor of the Guardian Order, he has always been a righteous conformist, excelling between realms of the living and the dead. While investigating a school suicide case, Zhao is attracted to the calm and reserved Professor Shen Wei, but the Professor seems to be rather fickle towards him…

- Description from Novelupdates

The king of assassins was reborn, mastering both alchemy and poison. Sitting inside the space, there was a ghost that loved crying.

Li Wen runs a game company on the verge of bankruptcy. This is a world where the game industry is very developed…

The picture quality of games produced by well-known companies is comparable to reality, and each masterpiece is the ninth art carefully crafted.

However, he found that in these games, the main character is strong and the enemy is weak, and the level can be easily passed without thinking…

There is no underworld game in the whole world?

How can I enjoy the ‘joy’ of the game in this way!

It is impossible to obtain real ‘happiness’ for a cool game.

He decided to let the players in this world enjoy the ‘joy’ of the game.

“I don’t know why, this game is obviously so dark, and it’s so depressing to play, but I just can’t stop!”

“Please be a human being!!”

Since then, there has been an underworld game producer in this world.

- Description from novelbuddy

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.