Fahla blinded sensors that detected large quantities of metal and energy, the main components of vehicles and bases.
Fahla required large amounts of water to prosper, so fahla groves had to be placed in lakes, large pools, oceans, or other large bodies of water to be effective. To mask a specific area, twice that area in fahla plants had to be present. The only source of fahla was the planet Pallaxides around Hoogra-D'En's secret base. It is unknown if any samples of fahla ever made it offworld to other planets.