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Intro. It is a war between the machines and humanity for dominance on Earth, years ago humanity was forced to abandon its stay on Earth due to the attack of the machines, this resulted in humanity being almost extinct, or at least so reports the "Bunker" , the space base of resistance of humanity created and armed for the defense of this It is close to the Moon and with the YoRHA Units, automaton models capable of confronting machines and returning the Earth to humanity

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