Dwarf

Long ago, the Dwarves inhabited all of Allatar, some of their great cities and catacombs still stand now thousands of years later as testament to their skill at building. Something in the distant past drove the Dwarves back to the mountains, where once there was a continent spanning empire, even before The War, all that remained were a few isolated city-holds, great halls carved deep into the bedrock.
They were drawn into the war, their craft and ingenuity put to good use in creating horrifying weaponry, and they were not spared from the consequences of the ending.
They have locked themselves in their halls now, admitting no one and having no contact with the outside.