The Reborn Otaku's Code of Practice for the Apocalypse - Chapter 189

In a future timeline, the earth was visited by a species known as the Slarkovs.
Having lost their home planet and in search of a new one, earth was the next habitable planet for them.

Humans and Slarkovs made a deal with each other in return for the Slarkovs living on earth.
The Slarkovs traded their technology and knowledge for a new home.
They were similar to humans except for some of them who had slight differences so fitting into the society wasn't a problem.
Over the years Slarkovs and humans began to mate with one another and reproduce offsprings.
This in turn created a new species known as the mixed-blood.
Centuries later mixedbloods could tap into their bloodline and perform unimaginable feats.

Gustav born into an age where bloodline determines everything, struggles to fit with a useless bloodline.
His bloodline only grants him the ability to change his hair color, destroying his hopes and dreams for a great future.
His fate is turned around when an unexpected situation leads to him finding a system that grants him the power to unlock and upgrade bloodlines by completing quests but he's baffled by two quests with a five-year deadline. Success will grant him unimaginable rewards...
But only one thing awaits him if he fails... Death!

Follow Gustav on his interesting journey filled with unprecedented adventures, danger and death, maybe?

When the last prodigy level esper on Earth disappeared, Earth was in deep trouble of becoming another species’ colony. The ordinary Han, with his intelligence and hardworking character, was able to make a fortune after “accidentally” stepping into the world of dark net, later purchasing an esper power crystal that brought him the ultimate power that changed the fate of the universe.

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.

“That monster’s prefix is two hundred meters long?!”“It’s back. Who can stop it?”Isaac never planned for Celestia: The Eternal Realms to change his life. The game promised 100% immersion, a completely realistic world powered by quantum brainwave interfaces. But the moment he entered the game, Isaac was thrown into an entirely new world, no longer the player, but the played. His character, a “Lesser Hyena-Wolf,” came with the dreaded “Weak” prefix, reducing his stats by 20%.Isaac quickly realized that this wasn’t a game he could simply log out of. It was his new life, and there was no escape. To survive, he had to evolve, to fight, and ultimately, to conquer. He knew the game inside and out, but this wasn’t the same reality he’d logged into. This time, he would have to become the monster, instead of fearing it.Every step he took, Isaac grew stronger. He realized that monsters weren’t bound by the same rules that governed the players. He could evolve, gaining new powers and unlocking Monster Reputation. With every kill, every victory, he unlocked a new level of power. The prefixes that marked his growth—Normal, Strong, Especially Strong—were a testament to his evolution. And the players began to whisper.