My interracial harem of beautiful queens - Chapter 135 The maid’s meeting

Violet skies, a world undergoing massive changes, a deficient moon, interlinking voids…
When the world experienced a cataclysmic event,the majority of living things ceased to exist. Although humanity survived by hiding in the last safe zones, humans had to face mutated dire beasts and colossal source beasts that could break through the space barrier and enter the earth at any second.
Luo Yunyang, a young man who grew up in those calamitous times, obtained an attribute regulator and set out to walk the path of supremacy!

- Description from novelupdates

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.

Admist the turmoil of a blood-soaked battlefield, General Hua Ren was perched on a horse, his once-pristine uniform now a canvas of rebel bloodstains. Lifeless bodies, a macabre mosaic of soldiers and rebels, lay strewn across the ground—some severed, others trampled beneath the hooves of horses.In the distant backdrop, a bomb erupted, rattling the battlefield, and in that fleeting moment, the General detected the scent.His Alpha.His heart raced as his gaze locked onto the most frigid, intimidating eyes he had ever encountered, and a sinking feeling gripped his stomach.Sheng Fei, leader of the rebellion, stood tall amidst the chaos, a sinister smirk playing on his lips. In a chilling display of power, Sheng Fei swiftly ended the life of a soldier, his eyes never leaving Hua Ren.The stark reality unfolded before Hua Ren, solidifying the bitter truth that their connection was entwined in the threads of enmity.He could never be the Omega to a Rebel AlphaOr so he thought.

A magical ring and a mighty spirit inside the ring, coupled with a genius who lost his cultivation and got named worthless trash. That’s Xiao Yan, the poor genius. You think Xiao Yan got it bad? Well, you clearly have not met Jing Yan.

Jing Yan was once the shining star of the whole East City. However, his cultivation dropped because of the Universal Ring that was left to him by his dead grandfather. Without anything but the Universal Ring, he will once more rise towards the top and beyond!

He is Jing Yan, The Universal Sword God.

- Description from Novelupdates