In the MCU/Marvel with the Omnitrix/Ultimatrix - Chapter 28: "Hulk Hero Not Monster!" ~ Hulk

Nagasawa crossed to Naruto Universe and was bound to Konohagakure.If Konoha is severely damaged and destroyed, Nagasawa’s lifespan will be reduced.He panicked at the thought of the upcoming Nine-Tailed Demon Fox's attack , and the thought of Konoha getting destroyed left him in despair.Fortunately, while bound to Konoha, he can obtain templates of powerful characters.At the beginning, He got the Whitebeard template! Since it's the Whitebeard from the Summit War of Marineford, he can use Tremor-Tremor Fruit's ability and Haki.Facing the Tailed Beast Ball, which terrorized Konoha Shinobi, Nagasawa leaped and shattered the Tailed Beast Ball with one punch!

A young man playing games in his basement is struck by a mysterious bolt of lightning, killing him instantly. However, he wakes up in the body of a disgraced young lord, now tasked with managing a ruined, crumbling kingdom. With no experience and a tarnished reputation to overcome, his future seems bleak.Fortunately, he possessed the Omnishop System, a mysterious tool that enabled him to purchase skills and supplies as well as upgrade his existing skills using points. Rebuilding the kingdom is no easy feat, but Alexander has his sights set on more than just survival.With ambition burning in his heart, he dreams of ruling an empire, if he can survive the challenges ahead.

Born and raised as a nameless shadow guard for his kingdom’s crown prince, his life’s purpose was to be used and discarded at the whims of his liege.

And his meaningless life ended when the gaze of a princess lingered on him for too long. The crown prince had him beheaded without a second thought, as if throwing out trash.

Transmigrating into the body of a baby girl, the nameless shadow finally had a name, a family, and a place to call her own. Throwing away his past, the shadow guard was now called ‘Emilia’, and walked on a new path to seek fulfillment.

It was not meant to be, however, as the girl whom she had loved with all her heart and soul ended up mercilessly plunging a dagger through Emilia's love-struck heart at the highest point in her life.

The crowd clamored at the ‘deserved death of the villainess’, and at that moment, the shadow could only wonder… why?

Why am I always the one to dedicate myself fully to someone, only to be thrown away like trash in the end?

And thus, as her soul floated away while cursing in resentment, ‘Emilia’ vowed to herself that in her next life she shall never be the one to fully dedicate herself.

Whatever she likes shall be held in her palm, and shall never escape.

The moment the vow was made, a self-proclaimed villainess system proposed to partner with her, to explore and conquer the worlds through their anchors—the heroes and heroines.

And by cultivating this energy, she shall one day go back. Back to the world she was born as ‘Emilia’ in, and face the so-called heroine once more.

The second time they meet, Emilia won’t be the one drowning in regret!

...

Author's Note: The heroines are not just trophies she’s collecting, only to be forgotten once she collects them. Each of them will remain relevant throughout the story. And it won’t become a mess, promise!

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

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