Battling Records of the Chosen One - Chapter 288 - We Shall Meet Again Someday.

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.

When a boy in a medieval fantasy world wakes up with the memories of his past life, he discovers a secret buried deep within his mind—a highly advanced AI companion. This AI, a relic of his previous existence, holds the knowledge of a futuristic world filled with technology, science, and innovation.Armed with this unprecedented advantage, the boy embarks on an extraordinary journey to transform his medieval surroundings into a thriving futuristic utopia. From reinventing agriculture to creating advanced cities, he introduces ideas far beyond the comprehension of his peers. But his vision isn't without challenges—power-hungry nobles, skeptical commoners, and ancient magical forces stand in his way.

[Warning: This story contains extreme violence, philosophical depth, psychological breakdowns, self-improvement, self-realization, and themes of maturity.]“Even Gods need character development.”That was the belief Pratham lived by—struggling, always pushing forward. Until the day he died, starving in a world too cruel to care.But death was only the beginning.He transmigrates and awakens in a multiverse as Leon. In this multiverse, the greatest threat to humanity isn’t demons or beasts, but Entities. In response, civilizations across each universe forged a single hope: the Entity Hunters Organization, training warriors to stand against the impossible.He had no magic. Just his will, his fists—and a little sister he swore to protect at all costs.Enrolling in the Entity Hunters High School, Leon finds comrades, purpose, and war. He fights beside them across different planets and universes, grows with them, laughs with them—then loses them all.Leon rises not as a hero, but something else.

Accidentally reborn as the son of the distant cousin of the Squib, the mother of Harry Potter’s friend Ron, and lived in this world as the second generation of Squib for eleven years.

He originally planned to be an accountant like his father in the future, but he didn’t expect fate to play a joke on him, and he didn’t know the slightest bit of magic, but he received the exact same envelope as his sister on his eleventh birthday.

Due to the expectations of his parents, he reluctantly accepted the reality, but inadvertently discovered another secret…

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