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In the Borderlands universe, a Siren is a woman with mystical, unknown backgrounds and incredible powers. They are distinguishable by the blue tattoos running down one half of their body. In Borderlands 2, we learn that only 6 Sirens can exist in the universe at any given time. During the time of Borderlands 2, we know of three Sirens: Maya, Lilith and Angel. The leader of the Crimson Lance, Commandent Steele, was eventually revealed as a fourth Siren. Although, she was killed at the end of the original Borderlands.
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