Dark Sun: The Scorched World of Athas
Shimmering heat mirages are not all the rise from the surface of the desert. At times, particularly at dusk, dreaded silk wyrms take to the air, slithering swiftly and silently through the darkening skies. With their keen eyesight, these beasts spy out prey. Appearing out of nowhere, like shadows becoming solid, the serpents dive down and strike.