Fribulan Lung

These "living machines," are somewhat akin to humans' argon gas rigs. They sit in the swamps and extract argon from gas vents. The Frib, however, use argon as a major component in building their bases. So a base with many working lungs will expand more quickly and its mother will birth soldiers, harvesters and ogres more quickly. So, destroying Fribulan lungs will slow their overall progress.