Akame ga Kill: Starting with Dual Kamui - Chapter 42: A Quilt

My name is Joelson, and I traversed across the world. I arrived at a continent of sword and magic and became a noble sorcerer.

This is the story of a young man who was reincarnated as a dragon with a near-insatiable curiosity. Initially sparked by questioning his own reincarnation, he quickly gets lost in the endless world of magic, using his deep understanding of advanced sciences to learn the laws and properties of a new type of energy known as mana.However, soon enough, the table would flip, and he would begin using that very same energy to expand his knowledge of science, to the point that he would begin questioning his own understanding of the world.Although not his original intention, with the combination of his intelligence, expanding curiosity, and the 'miracles' that occurred to allow for his existence, he quickly found himself climbing the mountain of strength as if it were a small hill before eventually climbing to a point where it seemed as if he himself was the peak itself.Even if.. that was never the case...There is mild gore, and profanity is 'censored' toward the beginning, but not later in the story.

Lin Xun unintentionally downloads a text game called “Book of Salvation”.Leveling up and taking adventures is just standard procedure.Not only can he bring game items into reality, but he discovers that he can also bring game characters into the real world…Although the game difficulty is hellish, luckily, Lin Xun has an unusual talent.While other Apostles can only use one game character…Lin Xun is hesitating over which one of the game characters he should use.While other Apostles are still using weak human characters...Lin Xun is already using powerful monster BOSS characters.…Then one day, when Lin Xun brings a terrifying BOSS into the real world...“Would you believe me if I said I'm here to save the world?”

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.