The Sand Worm stalks beneath the battlefield, hungering for prey.
Every now and then, a miniature sandstorm forms around one group of your ground units: either soldiers, reinforcements, mercenaries or Hero. Several seconds after that, the Sand Worm will emerge, mouth first, from the point where the sandstorm appeared. Every ground unit caught by the worm's mouth - friend or foe - will be instantly eaten. Giant Wasps, Ashbite and Bonehart are not affected. The worm then burrows again, and the cycle starts anew.
Beating Dunes of Despair without letting the worm eat any of your units grants the achievement Mua'dib.
- Pay attention to the sandstorms and move your troops accordingly; especially when the Sand Worm is targeting mercenaries: they cost money and cannot be easily replaced.
- Don't turn off the sound effects or mute the game to make it easier to identify when the Sand Worm appears. There is a rumbling noise signalling its arrival. It will always appear beneath a group of stationary troops.
- Both the Sand Worm creature and Mua'Dib achievement are references to the 1965 science fiction novel Dune. The Sand Worm looks almost exactly the same as its Dune counterpart in Dune II, while "Muad'Dib" is the title of Paul Atreides, the main protagonist of Dune, which refers to a desert mouse admired by the Fremen for its ability to survive in the open desert.