Be A Son-in-law After Cultivating Immortality - Chapter 10

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.

After his village was destroyed by an E-Ranked demon horde, Augustus was titled the failed lord and mocked by other noble lords.Until, he died.Augustus regressed with the knowledge of the future and his SSS-Ranked skill “Talent Evolution,” fighting to change the D-Ranked village of Iona into an S-Ranked Empire.Need resources? His villager's 10x Resource Multiplier Talent was evolved into 100x! Enemies coming? His champion's Two-Hit Critical Attack was evolved into a One-Hit Critical Attack! Gods? He reared a couple in his courtyard.While other lords slept on their villagers’ talents, Augustus’s villagers transcended gods. While they mocked him for picking a dead village, he would transform it into an oasis.

Earth is the human civilization’s cradle, but humans cannot possibly live within its cradle for eternity.In 2264, the first deep-space colonization spaceship of human civilization leaves the solar system and enters the boundless darkness…Zhang Yuan, son of the man behind the spaceship’s main control system, is one of the half a million volunteers to embark on the 20 light-year journey to a new planet.Follow Zhang Yuan on his journey of gaining new knowledge, exploring the unknown, and finding out what's the secret behind the intelligence enhancer his father left him.

“Ryan was transported to a world of swords and magic, and he discovered that he was contracted with a system that made him stronger as long as he continued to practice basic magic!

When everyone else was learning all sorts of fancy magic, Ryan was keeping a low profile practicing foundational magic!

“Ding! Congratulations to master for completing foundational magic training 10 000 times. You obtained [Spell Casting Speed X10]!”

“Ding! Congratulations to master for completing foundational magic training 100 000 times. You obtained [Complete Fire Elemental Magic]!”

“Ding! Congratulations to master for completing one million times of blade-drawing. You obtained [Domain of the Laws of Magic, Saint Mage Rank]!”

Thus, after practicing foundational magic for billions of times, when Ryan unleashed his foundational magic, he realized that no one could rival him!”