When speaking of Shadow Wraiths,i start to seeking the old mythologies and found something that maybe or maybe not suits the Species : "Revenants" (I was consider "Shades" at first,but it seems similar to "Haunts" a Minor Faction in Endless Legend)

probably suits the Faction whose mostly consists of wraiths,and when to thinking of space,nothing suit them like void (looks empty,but exist at the same time)

why'd i name it? i don't know,but it seems somehow suit the beings that look like a literal wraith (i think)