I Pioneered Scientific Magic - Chapter 145: Reference and Pi

The powerful have caused chaos for all that are lesser than them since the beginning of existence.This is the story about the truth that everyone knows but no one realizes.The story of a king who failed his duty, a dragon who lost what it held most dear, a beautiful girl who lost who she was and a fae that was once a queen.Cades Kirgun is an ehetrian child, one that longs to become an artificer.But his plans go awry as his whole world collapses and he needs to flee.How will he survive ?How will he overcome the challenges presented to him and overthrow those that have held the power for far too long ?This is the story of a king born from rags, a king that leads to people to fight for what they believe in, the crusader king.

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.

Having reincarnated into a different world, Murong Lin found himself utterly bewildered.The golden finger system informed him that he needed to eliminate the protagonist—wait, he wasn’t the protagonist?Innocently, Murong Lin turned his gaze towards the designated heroes, a butcher’s knife clutched in his hand. Regretfully, he realized he had no alternative but to end their lives if he wished to survive.Hold on, this pig was a protagonist too? And that tree?Without any choice, Murong Lin found himself forced down the path of bloodshed.

Yang Chan transmigrated into a Martial Arts World on the verge of a chaotic era. With mediocre aptitude, he can only rely on the Tai Chi Health Cultivation Skill and the attribute-adding panel from his transmigration, continuously adding points to improve his Cultivation, enhance his aptitude, and increase his lifespan. He first set a small goal for himself: to live for a thousand years.