I Am Such An Expert; Why Do I Have To Take In Disciples - Chapter 3 - This Master Is Unfathomable

Athar VonCruz, an orphan, had always been at the bottom rung of the society. He had been bullied, belittled and pushed down for his entire life.Beast taming in this world is not a hobby or a profession but is the only way of survival for a human and to gain power.Athar invests his entire life savings for one of the beast eggs; the only chance he has to rise and get ahead in his life.The egg cracks, and a creature of unknown potential emerges from it. In that pivotal moment, Athar's destiny irrevocably shifted. In that moment, Athar unearths a strange and wondrous secret; a hidden power that would become his ultimate trump card.Read how Athar VonCruz carves out a path out for himself and strives to reach the pinnacle of life.

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.

A Speedster in a Fantasy World

Once upon a time, a boy was referred to as a “War Hero.”

In another world called Aletia, the boy who had saved the Lost Kingdom, conquered their neighbouring countries, and led to the rise of a grand empire decided to throw everything away, returning to the modern era at the cost of his memories.

As three years passed, the boy who was happily enjoying his daily life was once again called back to the other world.

However, what awaited him was the Aletia of 1000 years in the future.

As his past glories became a “myth,” the legend of the youth referred to as the, “Twin Black Hero King,” begins.