averna Umbrae Torquentes, the Cavern of Twisting Shadows, is Domus Magna Criamonis and has the most potent magical aura known to Ordo Hermei. Carved into a mountainside about thirty miles southwest of Innsbruck, the conventum comprises a vast and bizarre labyrinth of caverns in nine regio layers.

Some caverns have been expanded from natural cavities in the rock, while others, and the various tunnels linking them, have been excavated. However, not all tunnels, and not all caverns, exist on all layers of the regio. Some tunnels only connect caverns on a few regio layers, and a few only exist on a single layer of the regio. The central cavern, however, exists on all nine layers.

Covenfolk and visitors reside in the outermost regio layer, the Extimum. Resident magi occupy sancta scattered throughout the maze of caverns on various regio layers. Currently, twelve magi Criamonis reside at the Domus Magna.