MTL - My Koi Sister is Three and a Half Years Old - Chapter 416 Heavenly Tuosheng

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.

Jiang Chen, son of the Heavenly Emperor, unexpectedly reincarnated into the body of a despised young noble, thus embarking on the path of the underdog trouncing all commoners. No one has the right to call himself a genius in front of Jiang Chen, as no one has a better understanding of the heavens than the son of the Heavenly Emperor. “Genius? He who adheres to me shall ascend. Those who oppose me can find solace in hell!’

In his first life, Victor was lazy, poor, and the ultimate gambler, but the Goddess of Envy gave him a chance.

[ Die and go back four years into the past to restart your life. ]

Victor lost all hope and killed himself, and so began his second and also the most miserable life.

He became rich and successful but soon his girlfriend betrayed him and took away all his fortune, having decided on a desperate act Victor came up with a plan to avenge himself.

Although his plan was successfully executed, Victor hoped that this time he would die once for all and forget the despair that followed him through his two lifetimes.

Yet as if to deny him of his salvation, he suddenly heard a feminine voice once again, but a different one this time.

[ Goddess of Lust, surprised by your actions, grants you a gift ]

[ Yandere system activated! ]

It was a turning point for Victor.

From now on whether it is a Goddess, a Vampire or a Succubus, no matter who it is I must seduce you or I will surely die this time!

An AI calling itself Schema has assimilated earth into its system. As a consequence, everyone gained access to status screens, power-ups, and skills. This AI turned these concepts from fiction to fact. It's easy to become intoxicated with leveling up and becoming stronger. To some, it's too good to be true like living out a dream.

For Daniel, however, it's closer to a nightmare.

He's in a bit of a predicament. Cracks in our dimensional fabric have unleashed terrifying beasts from dark, abyssal places. Schema organizes these cracks into dungeons, giving the native species of the planet a chance to fight back. Daniel finds himself trapped in one of these dungeons. Not long after, he discovers there's only one way out.