Planar Capstone

A Planar Capstone is a magical device that has thus far been found in all of the discrete areas of the Underrealm. Suffused with spells of warding and planar anchoring, the capstones seem to be the only thing keeping Emberglow safe from the unknowable hordes of Hellkind lurking just below the surface.

The devices were originally referred to as dodecahedra by Ser Loras Justinian and his party – an appropriate description of their shape. Approximately a third of a metre in diameter, the capstones are found in dedicated small rooms within all explored Underrealm locations.

Capstones levitate slightly from the floor and rotate slowly, surrounded by a shimmering aura that makes them appear translucent or even ephemeral on certain facets. For as long as they are present, the dungeon realms they inhabit are entirely cut off from Emberglow save for when a Lord's Crystal Key is present at the entrance to the realm. Their presence also blocks the use of certain magics that involve the Planes.

Unusual planar capstones
Planar capstones can also be found in more unusual locations – if indeed their presence can ever be considered 'usual'. These capstones operate in the same way as their dungeon realm counterparts, but the shards of the Underrealm that they isolate have remarkable characteristics.


 * Toltharien, the ruins of an old mage's college, believed to have been levelled by a magical accident but in truth brought into the Underrealm. A planar capstone stands in the entrance hall of the main tower.
 * Hag's Hollow, an ancient barrow full of the walking dead that dates to times before the mass immigration of humans into Emberglow. A planar capstone lies in a chamber deep inside the barrow, housed in a room clearly newer than the surrounding structure.