Gollaon moved quickly aside, almost skipping away as the black-dressed mage swept by.
Voddick watched them go. “What was that is aid of?” he asked once the wizard was out of earshot.
“Did you see? No shadow,” said Gollaon.
“That is not good.”
“Not good at all.”
Shadowstealer
These cloaks, if there are indeed more than one, are of a dark cloth that often seems black but occasionally other dark colors can be seen within. It never seems to wear or stain, always dark, always complete.
Sea of Stars RPG Design Journal 