The Most Generous Master Ever - Chapter 1046 Great Chaos

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates

The era of the great pirates.

The sea is surging, the strong are destroying the sky and the earth, and they are fighting each other. It really makes people——

Can’t get up!

I, Rusilu Cullo, twenty-four years old, my biggest dream:

Live this life safely!

- Description from novelbuddy

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.

Mediocrity is the normal state of most people, and some of them can’t even reach the normal state~ A young man from a small town, ugly and inferior, disliked by relatives and friends, mediocre grades…

All these changes started with a beam of light going to the university train, and the boy was bound to the high-quality male god system.

The days are getting more and more hopeful, and the system is really fragrant:

As long as you learn, you can modify your own bugs;

As long as you do good deeds, you can get corresponding banknote rewards;

As long as you are praised, you can get relevant talent blessings;

…

This, it’s hard not to love, okay!

- Description from novelbuddy