Deep beneath Valhalla, in the depths of the Myrkheim tunnels, lie the remains of a lost civilization. Metallic tiles imbued with strange runes line untold miles of labyrinthine tunnels and grand halls, centered around a mysterious and ancient site known as the Citadel. Though the Citadel has never seen sunlight, strange glowing mushrooms cast an eerie light. But there are other mushrooms as well… ones that seem to pull all light into themselves, obscuring those who venture near them from view