My Taboo Harem! - Chapter 319: Void Ice: First Element Awakens

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 crossing over into a world of magic, Dean Bruce was mistaken for a powerful sorcerer. Though he initially intended to sternly refuse the beautiful woman’s request to become her mentor, she offered him far too much to say no!Completely clueless about magic, Dean Bruce had no choice but to make up spells on the spot. However, when he saw the astonishing power unleashed by the beautiful woman after chanting his random incantations, he was stunned.The spells he had carelessly invented… could they really comprehend magic and even forbidden spells?As Dean Bruce ascended to the pinnacle of magical prowess and became the Archmage, he candidly answered a reporter's question during an interview with the Alliance: “ never understood magic. I just made up a few incantations, that's all.”People were in awe of him—this, they believed, was the true humility of a Grand Archmage!

Growing up in a facility that turned children into weapons, Subject 42 never knew freedom; only survival.So when a strange creepy entity offered him a second chance in another world in exchange for one mysterious task, he took it. Even if that meant living in a world that was drenched in curses, ruled by ancient gods, and shaped by powers no mortal should touch.Reborn as a Moon Elf, a being of myth and moonlight, he finally thought he could live the life he was denied.But the task he completed set something in motion. Something that he couldn't outrun.Witness, as his fate twists and turns, as Noctis moves through this strange world in search of a respite...

Xu Yiyang, who was only late in his life when he was middle-aged, returned to 1999 in a dream.

At the turn of the millennium and the turn of the century, he realized a truth:
Not only to be famous early, to start a business and make money, but also early!
………………
New book uploads, new stories, new voyages,
Hope you all support!

- Description from Uukanshu