http://www.principiainfecta.com/archives/2006/07/the_hagfeast_of.php
The peasants name this festival day the Hag-feast, for of the holy works of Hasem of the frozen Kalask realm, her Purgen upon hags of the ice-forests is most told in Witan. Lay-brother Wagen has spoken wroth and rancor of this complexion of a holy festival, for he is oft to preach against peasant fantasies of hags in the Rur realm forests and Unhallowed forgen-ruins. Yet each thrice-year, the Lay-brother is laden once more with festival-works and the dreams of peasants ever more embellished.
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A festival procession of peasantry masked as hags of the forest, loud in the chill vault-ways, came upward from the great-portal at dusk, as much as for each Hag-feast past. Yet Lay-brother Wagen had caused the old wooden feast-works to be prepared once more; the procession came atumble upon the broad-deck before twenty lusty peasants within a fulsome image of the Anointed Hasem's war-barque Revesk. With great fervor and strength, whither and back they blundered, with shouts for great-cannon and pennons for holy Prophet's Fire upon the false hags.