Fierce Ex-wife: President, Please Be Careful - Chapter 13

In a world where the boundaries between dimensions are thinning, a young man named Kael Ardent is thrust into the Eternal Nexus, a realm where countless worlds converge. Here, the laws of reality are dictated by Aether, a mystical energy that fuels both creation and destruction. Kael discovers he is a Nexus Warden, a rare being capable of manipulating Aether to bridge worlds and command the forces of the Nexus.But the Nexus is not a place of peace. It is a battleground for Eldari, ancient beings who seek to control the Nexus and use its power to dominate all existence. Kael must navigate this treacherous realm, forge alliances with warriors from other worlds, and unlock the secrets of his own latent powers. As he grows stronger, he uncovers a prophecy that foretells the rise of a Prime Warden, a hero who will either save the Nexus or doom it to eternal chaos.

“I'm one game away from reaching the master rank! I'll do it tomorrow, though. A true gamer knows when to refresh his mind and increase his victory chances!”Adam smiled in anticipation as he went to sleep on this special day.However, he could never have imagined the surreal awakening that awaited him.“What's wrong with my voice?!”“Claws? A tail and horns, too?”[Welcome to the demon realm. You have been selected to reincarnate as a Lord. Conquer this realm of fire and ashes, become its uncontested ruler... or die trying.]Reincarnated as an imp in the cruel demon realm, at the borders of the mythological demon Baal's territory, his life seemed doomed from the start.However, determination sparkled in his eyes as against all odds, he defiantly proclaimed.“No matter who decided to make me start as an imp, watch as I turn into a veritable devil. Even Baal won't hold a candle against me in the future!”Equipped with his unique talent, he started his lord's journey, ready to evolve and prove to those strange realms that demons were more than violent and deceptive creatures... at least he would try.

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.

This is a story of a modern man returning to ancient times, returning to a real world without any extraordinaryness, and slowly rising by relying on the ability to attribute all data.

- Description from novelbuddy