Steel, Explosives, and Spellcasters - Chapter 3 - 1: The Last Swordsmanship Competition_

She remembers him because of the mole at the corner of his eyebrow;He remembers her simply because she is her.Every passing encounter becomes a story in the memory,And you are the ending of my story.

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 mysterious game called “Forsaken” descends upon the world. Players can slay monsters to extend their lifespan, or consume their lifespan to extract game abilities into reality!As extraordinary powers emerge, chaos spreads across Blue Star, plunging the world into disaster.In his previous life, Qin Feng, along with his cousin Qin Xiaoyou, rose to become one of the top hundred global powerhouses. But in the end, he was betrayed by his star-struck sister, who gouged out his 'Ancient God Eyes' to gift them to her idol.Reborn in a new life, Qin Feng chooses to walk alone!His sister? Let her be damned!Thus, a god-level assassin with no shadow or form is born.He is the Shadow, dancing in the dark with his blades. Death and slaughter bloom like art in his hands...Surrounded by countless corpses, he will ascend to the throne of gods!P.S.: Skills evolve infinitely—permanent invisibility, one-hit kill, hundredfold drop rate, divine slaying with ease...

God gave me one more chance and finally came back after four hundred years.

As soon as I realized I returned, I decided that ‘no one should have pride.’

My goal was to destroy the country. So, I grew up with a genius prince who lived in hiding before returning.
He took up the empire for me and I left him for him to achieve his goal.

‘I came to pick you up Charlize Ronan.’ Dylan, who became a perfect tyrant after a few years, found me after searching all over the continent.

‘Why did you flee and run away?’