The Yun Family's Ninth Child is an Imp! - Chapter 6368 - , you are an imposter

A young boy, Asuma Haruto, is transferred to another world. Without having any means to return home, he has no choice but to live in this parallel universe.

Armed with only his knowledge of making soap, will Haruto be able to safely make a living here?

This is a story about how our protagonist creates his own business out of his hobby of making soap and then gradually manages his business and gets rich.

Li Ke Lin (also Li Colin), a Chinese office worker, woke up to find himself suddenly no longer Li Ke Lin but instead Colin Lee, son of multi-billionaire in America. Having taken over the body of Colin Lee and carefully imitated his manners and bearings, his next goal is to inherit his father’s wealth. However, when his father lists the condition of marrying a woman who feels repulsed by Colin Lee’s (not Li Colin’s) dalliances, and whose very nature is the complete opposite of Colin Lee (not Li Colin), what must he do to gain her affection?!

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.

Chi Xiaochi: fourth-rate citizen at birth, three-time award-winning film emperor, second-rate temper, first-class looks. He crawled his way out of hell on hard mode to become a winner at life.

Then, he was smashed into a vegetative state by a chandelier.

061: Hello, here’s a brief rundown on the scum gong reconditioning system. This system measures the regret level of the scum gong. Every time their regret level reaches one hundred points, you will be able to leave the current world. A friendly tip, usually, through dedication and self-sacrifice, our employees slowly foster a sense of dependency in the scum gongs, gradually making it so the scum gongs can’t live without them.

Chi Xiaochi: How many regret points is a complete loss of reputation and standing worth? How about a fall from grace? Or wanting something but never being able to obtain it?

061: ……

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