Rock spools were giant, flying predators on the planet Karagula. They were quite common in the mountains. They were resistant to the scorching temperatures of the planet and had tough, leathery wings and hide, sharp talons, an ear-piercing scream and a revolting smell. Their one weak spot was a soft, unprotected chest. A single targeted shot from a float-stone sling was enough to bring one down. (PROSE: The Colour of Darkness)