Firefly

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10. The Reavers (Firefly, Serenity)

Worse than the completely inhuman are those who’ve lost their humanity. In a world with no alien species, Joss Whedon gave us something more savage. Cannibalism has always held a special fright in our culture. If we indeed are alone in this world, that doesn’t necessarily mean we’re safe.

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Click on the link for mroe :

http://www.pastemagazine.com/blogs/lists/2009/04/best-villainous-species-in-all-of-science-fiction.html