MTL - I Wield a Sword at Hogwarts - Chapter 677

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.

In a world where kingdoms rise and fall, a seasoned player unexpectedly finds himself transmigrated into the very game he once mastered—Caldera. However, his new life as a ruler comes with a crushing twist: severe debuffs and harsh restrictions on his talents make survival nearly impossible. Against overwhelming odds, he fights tooth and nail to carve out a legacy. Despite his brilliance in strategy and marvels in combat, failure becomes his ultimate fate.

[STOP STEALING MY WORK, RULATE SITE BASTARDS]Aron died in an underground fight arena, only to wake up in Marvel World with an OP power similar to All For One. But in this world, he is a clone, saved by the X-Men. Follow, Aron's new journey as he tries his best to fit in this world of endless chaos.The biggest question is if he is a clone then where's the original body?[Timeline: AU][Harem> So, please, if you aren't into it, don't read.]...[The cover picture is AI made]...[This is not a translation.]Support link: pat eon.com/UnknownMaster[15+ advance chs] [No double billing]

Baek Ain is your typical lazy guy.

He graduated from university at age 22 with a random degree he chose out of boredom and stayed single because fate decided so until that event happened.

“What? Where Am I??”

After a horrible incident, Ain transmigrated to another world. Or precisely to be a villainous and mobs character.

He died countless times because of the world's protagonists, gathering hatred toward them.

“What the fuck! What do you mean I stole your wife? I've been single since coming into this world!!”

“Hero, please save this world.” A goddess is begging me to save her world from the Demon Lord.

“Wait... Begone thot! That Demon King is my younger sister from 69th Transmigration.”

“How dare you!”

A beautiful heroine is hugging me from behind, wishing to accept her feelings.

“Shoo, Heroine! I don't need useless baggage with me. Side characters are better than you!”

And so, Ain's journey began to end this shitty transmigration cycle.