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The Animus, which is used to read the genetic memory of a person, is named after Psychologist Carl Jung's theory of the collective unconscious, with the Animus being the masculine inner personality for females.

A few of the female characters in the series are even named after the levels of the anima (the feminine inner personality of males). These are Eve, Maria and Sofia, with Helen being the only one without a character.
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In every Assassin's Creed game, the main characters you assassinate were real people, and the time and location of their death is accurate.