I Stream DC on Marvel - Chapter 464 - Invincible: Omni-Man is a Monster, The Deal with Cecil Stedman, The Mauler Twins Attack The White House, and The Regulator.

I, an ordinary high school student, Kimizuka Kimihiko, who easily gets involved in things, was appointed to take care of mysterious attache cases by mysterious men in black suits. After meeting a beautiful angel-like detective girl, named Siesta in a hijacked plane, I became her assistant.

And from there–

[You deal with the beehive, and I’ll restrain the enemy.] [Don’t make plans that make me the victim.]

We had those kinds of foolish conversations, all while being completely broke every day and fought against . Even when there were hurricanes, the weather-beaten duo sleep past it. Sometimes when we saved money at a casino, we would jump around on the beds at a resort hotel, only to be broke again the next day. We would walk through deserts, traverse through jungles, conquer mountains, cross oceans– The great detective and her assistant would go through these dazzling adventures–

Until she died.

And this story starts from 1 year after that incident.

I’m the only one who’s left, but I carry on her remained wishes.

This story is far from over..

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.

[Post-apocalyptic + System Space + Stockpiling + Base Building + Strong Female Lead + Reverse Harem + Not a Mary Sue]Who says a five-year-old can only be a burden?Cloud Xiaoxiao, a formidable survivor in the post-apocalyptic world, is reborn six days before the apocalypse hits. Unloved by both parents and unwanted after their divorce, she decides to take matters into her own hands.At just five years old, she goes on a rampage. She empties out her father’s supermarkets and 4S car dealerships, landing him in the hospital.Armed with a super system in a world ravaged by zombies, extreme temperatures, and acid rain, she hoards enough supplies to last several lifetimes. She becomes a base-building maniac, constructing the strongest fortress in the post-apocalyptic world.Sunny Boy Next Door: “Little one, want big brother to sing you a lullaby?”Unlucky Bandit: “Kid, what do you want? I’ll get it for you.”Cool Big Brother: “Don’t be afraid. I’m here.”Yandere Hottie: “Little one, call me big brother and I’ll kill them all for you. How about that?”Hot-Tempered Brawler: “Shorty, who’s bullying you? I’ll beat them to death!”…Cloud Xiaoxiao hastily raises her hand, “Stop, stop! I can take on ten at once!”“Whoever dares to bully me, I’ll finish them off myself!”(This story has no romantic pairings. Readers who mind this, please be cautious.)(The female lead appears innocent on the outside but is actually a wolf in sheep’s clothing. Her personality was shaped by the post-apocalyptic world, growing beyond the bounds of normal rules. So she’s a bit ruthless, a bit wild, a bit wicked…)

When opened his eyes, Lin Tian realized that he was reincarnated into the modern cultivation world.

Seeing this person's memory, his expression became gloomy because his identity is a young master from a rich family.

Knowing this, some people might be happy, but not for him.

He had read many modern cultivation world theme novels.

Doesn't the young master like him is a stepping stone for the protagonist, and had a tragic ending?

Just when he was really desperate, suddenly the system came.

[Ding, congratulations to the host for binding the destiny villain system]

[Beginner's prize has been distributed]

[Congratulations to the host for obtaining a martial emperor level cultivation base]

Cool, just slumped, but now invincible?

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First of all, this novel doesn't have any elements of a brainless Harem, our MC will not be like other MC who every time he goes somewhere, he will bring another woman.