The official Dragon Age page has been updated with new information about a strange creature, the Rock Wraith:
Dwarven legends tell of dwarves so corrupt that even the Stone rejects them. Doomed to wander the deep roads in an undying half-life, these creatures are known as Rock Wraiths, and they are creatures of hunger, wrath and little more. While it's commonly held that Rock Wraiths are myths, every so often a survivor, often half mad, staggers from the deep roads whispering of living rock assembling itself into a twisted shape shifting parody of a humanoid creature, and of baleful eyes glowing in the dark.
You can see a screenshot and concept art here