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Intro. (Human/Scientific User) During the war humans designed a series of robberies that we call V "Machines" to help in wars, making them perfect machines for killing. When humans discovered that the big one was the most powerful fuel, they used it to power machines. After the war, most of the population became extinct and the few human groups that remained were dedicated to maintaining these machines and preventing them from continuing to kill people, because by feeding on blood they could generate an uncontrolled massacre. They began feeding the machines artificial blood to keep them on.

V2 Ultrakill (Human user)

@Andrea