Don Mazure is the Ghost of a long dead dwarven Lord of the Dwarfhold of Egregor. He never inherited anything because Egregor was lost during the Shatterwar, not through Orcs but because the Dwarves from Egregor dug too deep and released some unknown horrors from the depths (or so they thought, it was actually a plot by Delvash). He is also a member of Swayne's deadly riders and rides a pony that has to be pretty much fearless to let a ghost ride it (now ridden by Angel). He was cursing in a very dwarfen-like manner.
Don Mazure was mechanically a Whisper demon but reskinned as a Ghost, able to confuse anybode in a 60 feet range and using an ancient dwarven weapon instead of touch attacks (the attacks also benefited from his enchanted shield that gave him a respectable armor class and +2 damage to spells, that applied to his attack.) His Incorporealness didn't help him much because he fought against Black (who granted him his second death) whose Ghost touch mace touched the ghost right in the face.