Library of Heaven's Path 2: Eternal Fate of the Heavens - Chapter 513 - 9 Leaving

Huang Dan’s pain nerve is innately different from the ordinary people. A little tore in his skin can cause him to sweat all over his body painfully to the point of him unable to make a word out.

Somehow, he began to cross world, following Mr. System to do the tasks…

In the first world, Huang Dan realizes what it means to die painfully and to live to die again.

TL’s summary:
MC suddenly transmigrated and is bind to a system, requiring him to solve mysteries. Born with a higher degree of pain sensitivity, he met different people in the different worlds and learns what kind of emotion smiling is.

- Description from Novelupdates

A girl Alicia lived as an orphan in a world of sword and magic Ciel.

One day, she learned that she was an “otome game’s heroine”. Even her parents’ death was simply a part of the scenario. Alicia judged the heroine’s setting as 「nonsense」and discarded it decisively. She introduced herself as adventurer 『Aria』, gradually mastered multiple weapons and magic, and grew to become the 「Ash Crowned Princess of Slaughter」! But, by accepting a request to guard the “villainess”, before she realized it she got dragged into the stage where nobles quarreled against each other――？

「I am “I”. I’m not a game character!」

Create weapon! Train your body!

Survive the fighting against powerful enemies and smash apart the otome game!

A sublime and exhilarating other world battle fantasy with charming fighting heroine!

On the will left behind by the 14 year old suicide victim K:

“Taku Sugawara is the devil. Nobody should believe his words.”

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.