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Hallow's End marks the day the group of Undead that would later be known as the Forsaken broke free of the Lich Kings dominance and once again regained their free will. They celebrate this occasion by setting fire to a wicker statue after a short speech from Sylvanas herself and smearing the ashes across their faces.

Why the Alliance -- or, for that matter, the other Horde races -- also celebrate this event is unclear.

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