Voices from the spirit world can be heard through the dark
  winternights, the heartbeats of the spirit. It is the holy twelve
  days of Yule. Dark shapes can be seen in the sky; riders of
  death. They suddenly charge down from the clouds in wonderful
  wilderness; kings and chieftains, thieves and murderers - all in
  the same phalanx, drifting mysteriously through the air on spirit
  horses, arriving when least expected. Black shields, furs from
  bear and wolf, shining blades, open wounds and ropes still tied
  around their necks; they are Wuotan's pack of warges, the undead
  and the dead - the immortal warriors of Ansuzgarda! The
  werewolves haunt the sacred twelve days of Yule in packs, looking
  after the living; hail the sacred traditions, hail the spirits of
  the dead, hail the holy ritual of Wuotan, or face the wrath of
  the Ansuz and the hooves of Sleipnir. Face the Ansuzgardaraiwo!