I had a role (albeit unsuccessfullt) where i played Tharf,a svirf thief trapper-path whose belief was that he was essentially a ranger of the underdark, the thief skills being more suited to hiding in the underdark etc than camouflage. His sphere was earth and was dedicated to hunting drow and duergar who thoughtlessly mined the earth for it's gem. He believed the stalactites etc were like trees but even older. Tried to get into Sylvan but failed being unable to get Imm approval despite the tacit agreement of the mortal leaders

It was my belief that essentially all svirfs were similar, dedicated to the Earth as the embracing mother, which concealed them from their enemies in the underdark. for svirfs I thought minig was the underdark equivalent of deforestation.