Comprehension Ability: I Forge a Villainous Longevity Family - Chapter 5: No More Pretense, Let’s Lay the Cards on the Table and Go Big!

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.

Betrayed. Ridiculed. Killed.That was my past life.I trusted the wrong people, and they buried me for it. But fate wasn’t done with me yet. When I opened my eyes again, it wasn’t in my old body—it was in a world overrun by the undead. And this time, I was one of them.A fucking zombie!But I’m not like the others. I think. I feel. I remember.What’s this voice in my head?[Welcome to the Silent Requiem System!]The system feeds me power, unlocking missions and skill buried within this body. I have one goal: rise in rank, take control, and make sure no one ever tramples me again.The humans I move with have no idea what I really am. To them, I’m just another survivor, clawing my way to the top. But in battle, I use my abilities in secret—manipulating the undead, eliminating threats, and turning every fight in my favor.But rumors are spreading. There’s talk of an undead hiding among them, unseen and unstoppable. If they find out the truth, they’ll hunt me down like a monster.And my past? It’s here too. The people who betrayed me in my last life are standing right beside me, unaware of who I am. But I remember them. They turned on me once—I won’t give them the chance to do it again.Then there’s him. The commander of the city, sharp-eyed and ruthless. He’s watching me too closely, asking too many questions. If he figures out the truth, I’ll have to make a choice: eliminate him, outplay him… or pull him into my trap before he can destroy me.Because in this world, power is the only thing that matters. And this time, I refuse to be at the bottom.***“How did you survive when everyone else died?”I guess death just didn’t want me.“Why do the zombies ignore you?”Maybe I just have a face they don’t like.“You were just a nobody yesterday—how are you suddenly so strong?”Hard work, luck… and a little bit of hex.“Why do I feel like I've seen you somewhere before?”Déjà vu’s a funny thing, isn’t it?“What are you?”Wouldn’t you like to know?

I am a holy knight. To be precise, I am the Church of the God of Light’s Sun Knight…in training.

The Church of the God of Light worships and serves the God of Light, and theirs is one of the three largest religions on this continent.

As the whole continent knows, the Church of the God of Light has the Twelve Holy Knights, and each one has his own unique personality and features.

To be the Sun Knight is to have shining golden hair, sky blue eyes, a compassionate nature, and a brilliant smile.

…even the Sun Knight-in-training is no exception.

The 38th generation of the Twelve Holy Knights have completed their term of office, yet the time for the 39th generation to take over is still far in the indefinite future.

The Judgment Knight is brash and easily angered; the Storm Knight and the Leaf Knight are always fighting nonstop, day and night.

Since childhood, the Sun Knight-in-training has watched the others grow from kids into adolescents.

What must he do in order to become comrades, who will fight through thick and thin for each other, with this group of “younger brothers”?

“Benevolent God of Light, may I ask when I will complete my training that has taken more than ten years?”

Childhood sweethearts.
The most popular person in school is my childhood sweetheart.

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