Duepra Gairus (known also simply as Gairus, or Pfalkhair to the Erechai dwarves) was the patron deity of dwarves and some loyal dwarf-kin.
Gairus' stewardship of dwarf-kind began millennia before dwarves emerged as a distinct race, when he began to watch over the Dueva - the ancient ancestors of Dwarves, Giants, and their kin. In time, Gairus came to fear that the deepest of Duevar burrows would soon breach the Underdark, and that the dark energies of that place would seek to corrupt them. To prevent this, Gairus drew great masses of rock up, away from the boundaries of the Underdark, pulling large swathes of the Dueva and their burrows to safety. In doing so, Gairus had created the mountains of Auriin. It is said that Duepra Gairus was also the creator of the Heartstones of the mountains, whose purpose it was to stabilise the mountains and prevent the Duevar burrows from falling back to the underdark.
Appearance
Pfalkhair appeared as an idealised Dwarf. Of course, such an image would vary depending on the audience, but most traditional depictions of the deity are of a Dwarven man, slightly taller and broader than average, with impressive, braided head- and facial hair.
Name
The names Gairus and Pfalkhair translated approximately to "Mountain King" and "Mountain Raiser", in Orrik and Erechai Dwarfish respectively, with the element gai-/-khai- translating to "Mountain" in both languages.
In the Erechai name, the deity was venerated as "Mountain Raiser", with pfal- being a form of the verb "to raise", and the -r suffix forming an agent noun; the full name thus translating loosely to "Raiser of Mountains".
The Orrik name appended the element -rus, which meant "king", resulting in the meaning "Mountain King". This title was often used alongside a second name, Duepra, which translated to "Father of the Dueva".