Icefell Vaults
From Age of Sigmar - Lexicanum
The Icefell Vaults of Shyish were an ancient prison constructed by Nagash to hold the Winter Gods, ancient deities of ice. Myths among the Beastclaw Raiders claim that their ancestors freed these deities while in search of food and in doing so unleashed the Everwinter upon themselves, though this is but one of many myths about the origin of the Everwinter.[1a][1b]
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