Geheimnistag

Geheimnistag, also known as Geheimnisnacht Eve is a day that marks the time of the full moon. This holiday does not fall on any particular day of the calendar; the Day of Mystery, also called the "Floating Holiday", occurs when the twin moons Morrslieb and Mannslieb are both full in the sky. This occurs only once per year and is considered a time when the veil between worlds becomes thin, sometimes dangerously so. The Day of Mystery is dedicated to Morr, and many strange and unique festivals occur on this holiday throughout the Empire. Auguries are commonly performed, sometimes with spectacular or terrifying results. Humans take this day to pay homage to their ancestors, and sometimes these spirits come back to converse with the living (see Ancestor Spirits).[1a] 

Totentanz - taniec umarłych [Vampire Wars p. 108]

Geheimnisnacht 

The dark moon Morrslieb is full only twice a year, and one of these occasions marks its perigee. This night is known by many names: Geheimnisnacht in the Empire and Winter's Eve in Bretonnia; it is Twilight's Tide to the Elves, and Ar'Uzkul to the Dwarfs. On this night, sensible folk lock their doors and bar their windows, but for the followers of the Dark Gods this is a night of celebration. Morrslieb is accursed, a moon formed from material cast into the skies when Chaos first burst upon the world. Its proximity strengthens the Winds of Magic, weakening the borders between reality and the Realm of Chaos. On Geheimnisnacht, small rifts become large and large become immense, allowing thousands of Daemons to walk the mortal world for one night of mayhem and destruction. Morrslieb's chaotic orbit means that Geheimnisnacht never falls upon the same night in subsequent years, but mortal folk take care never to be surprised by its onset. Defenses are strengthened on this, the unholiest of nights, with special care given to those places rumoured to hold the favour of dark powers.[2a] 

In the Drakwald and Mousillon, peasants abandon their hovels and take shelter in castles and fortified inns. In the Ogre Kingdoms, vast cauldrons of bloody meat are sacrificed to appease the Great Maw and secure its protection. Beneath Zhufbar, ill-famed caverns are sealed tight by Runesmiths, their exits guarded by dour Ironbreakers and eager Slayers. Across Ulthuan and in the depths of Athel Loren, prayers are whispered to Isha and Asuryan in the light of the sacred phoenix flames. Rich and poor, young and old; all hope that the evils of Geheimnisnacht will pass over them; all hope that the night of evils will leave them unmarked by its infinite malice.[2a] 

On Geheimnisnacht, Sylvanians light a candle for each dead family member and then place the candles in the windows of the rooms where they died (family members who died outside the house have their candles placed on the doorstep). Some unlucky villages are so brightly lit on Geheimnisnacht it seems like daylight.[3a] 

Eventually darkness retreats from the sky. Morrslieb begins its slow wane and folk venture out in the new dawn. Some discover neighboring towns razed to the ground, no trace of the inhabitants to be found save for blood on charred timbers. Others take axes to trees that have twisted into unspeakable shapes, burn crops rotten through with pestilence or empty barrels now choked thick with diseased blood. All give thanks to have survived another Geheimnisnacht, and fearfully begin counting the days until it is upon them once again.[2a] 

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