Reborn As A Ghost: Time To Build My Undead Army!

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The Original Nightmare Curse, an eldritch entity born from this world's life itself, emerged from every single accumulation of fear, from the most primordial bacteria to the most advanced living beings, such as humans. This planet originally had no life, but through a series of coincidences and the right conditions, life was born, a spark ignited by countless chemical reactions within the boiling seas.

From this spark, life expanded into countless other living beings through eons. Despite taking so long to evolve to this point, every lifeform, even the most primitive, possessed an instinct: the desire to live and the fear of death. Live to reproduce, live to not die, eat to not die, and more.

Death was the end, and every living being feared death. This fear became a force, generating a chemical reaction within these living beings. A tiny black particle was formed, unique to this dimension. This small particle had nowhere to go, as no other particle could assimilate it.

Drawn by the planet's gravity, this particle accumulated in its hollow core. Over billions of years, one tiny piece at a time, every day, every night, the more living beings existed, evolved, and became more complex, the more complex their instincts and reactions became, and the more intricate their fears grew.

Through this complexity, through this reaction to fear, these particles continued accumulating. Born from living beings, they too were somewhat alive. Each black particle combined, forming a massive accumulation. Incompatible with all other particles, it distorted the very membrane of the universe, tearing it apart and creating something unreal, supernatural.

The Nightmare Dimension manifested from the Curse of Fear that all living beings shared, a living being that was neither living nor dead. A "thing" that continued existing and expanding through eons, its growth accelerating rapidly upon the birth of humans, the most emotionally driven beings in the world.

Its growth, in that moment, surged through the roof. It didn't take longer than a couple of million years before it gained consciousness and self-awareness through the absorption of Human Fear Particles, accumulating and giving birth to Nightmares.

Its first desire?

To eat.

It wanted to eat, to grow bigger, to develop more. This hollow planet was this entity's cocoon, no, its egg, and all living beings on the surface existed to feed it. To eat more, Nightmares were given form. The fears it absorbed from humanity were shaped as supernatural living beings, piercing through the membranes of the universe using the Fear Particles, which were rejected by other matter as if they were antimatter itself, tearing open cracks through space, creating Nightmare Realms born from fears.

But that wasn't enough. Nightmare Demons were created even earlier, stronger embodiments of fears and nightmares, refined into intelligent beings, the strongest elite of this living being, of this Original Curse, the embodiment of all living beings' primordial fear. The second most terrible accumulation of fear became the first Nightmare Demon, and the strongest, the Nightmare Demon of Death. He led his brethren, obeying his master, the true entity beyond Nightmares.

At some point, it was feared by the Nightmare Demons as the "Origin of all Nightmares," their one and only deity, the supreme being that should never be talked about or even joked about, as those who dared to do so were swallowed by its darkness and disappeared instantly. An eldritch monstrosity born from living beings themselves, not the void, an Outer God like no other.

The {Original Nightmare Curse}.

With the death of its Herald and Avatar, the Nightmare Demon King of Death, it realized it could no longer take things easy and rest while its extensions devoured the world for it. As extensions of its very existence, anything a Nightmare or a Nightmare Demon devoured was also devoured by it, making it stronger. The Nightmare Demons, however, were not that patient. They devised a plan to take over the entirety of the planet's surface and feed humanity to it to accelerate its birth.

However, due to the invasion of Nightmares onto the surface, humans had adapted to this supernatural energy. Some survived the Fear Particles and assimilated them into their bodies, crystallizing these particles, refined further by their own emotional energies, into Dream Hearts. These Dream Hearts formed embodiments of their own emotions, fears, or dreams: Dream Weapons.

Through this power, these people fought back against the seemingly immortal Nightmares, who were immune to gunfire or even atomic bombs, giving humanity new hope. The more Dream Warriors were born, the stranger their Dream Weapons became. Over the years, some were born with a power that could even threaten the Original Nightmare Curse, which was incapable of believing mere humans could manifest a power stronger than its own.

But it was wrong. In the last battle to protect humanity and Earth, the person Maria replaced, whose name and origins are now forgotten by the world, used the power of her Dream Weapon, sacrificing her life in the process to lock the entire world into a Temporal Loop, the strongest Dream Weapon capable of manipulating time, one half of another that her sister possessed.

With this power, she delayed the inevitable, stopping the Original Nightmare Curse from destroying humanity and being born, resetting the world and its time once every seven days, just the day when the Nightmare Demons took over the planet.

However, this brought a terrible drawback. Some people who died in these loops would never return in the next loop, and memories of them were forgotten, along with her, the one who saved everyone.

This caused an even stranger phenomenon, as an alien force of unknown origin began to intervene in this world, sending souls from other worlds to replace those who could not return to the next loop. None of them, however, could ever be a threat or stop the inevitable.

Until now.

Finally, in the very last loop, as her very existence was fading away and the temporal warping abilities of her Dream Weapon were disappearing, these new visitors, replacing all those that had disappeared through the loops or were forgotten, emerged. Unlike their predecessors, however, they were not weak and came from a magical world where they had already grown to a tremendous degree.

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