World Development System - Chapter 323: 254. Chaos at the Plaza Part 2.

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.

On earth, Felix is just a normal guy, a bit of a loner but otherwise normal. In the multiverse, under the rule of The System, he's a caster. Fascinated by magic and hungry to learn, grow and discover, this series follows Felix on his adventures through the integration and beyond.

I thought the world was vast, for me to wander, but now, it has only become a cage. For a life unhindered, I wield a single sword to pierce the ninth heavens. People find me displeasing, but there’s nothing they can do. That’s the kind of life I love!“Stop! I paved this path and I planted these trees. If you want to pass through…”“Brother, I come from the Dustfallen sect.”“What? The Dustfallen sect! Piss off!”This pitiful sect was so poor to the point where even bandits did not want to waste time on it. However, how could this sect, these nine measly people, be ordinary? What you see is only what they wish for you to see. What you can’t see is the truth!Mu Yu—a young human boy with the powers of elemental demons—accidentally joins the impoverished Dustfallen sect. The sect that even bandits did not want to waste time on was actually hid great talents, concealing a huge secret! You look down on my sect? Then that’s your ignorance!

As a eunuch, Tian Qi’s ba zi* was harder than diamond-plated gold drill. Although her ba zi easily brought an end to three consecutive masters, the Emperor was not afraid to be the next casualty and got her to serve at Qian Qing Palace.

Although His Majesty looked like a handsome gentleman, his behavior was more like a hooligan. Once, the Emperor touched Tian Qi’s lower abdomen and started to wonder at the amazing flatness of the area…

*八字 a Feng Shui term that refers to one’s date and time of birth, or the destiny that one is born with

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