The Phase Field is a Scrin support power. It could temporarily render any friendly vehicle nearly indestructible by means of putting them out of sync with the physical world, although it also prevented the vehicle from attacking. The affected unit was still vulnerable to EMP or being crushed by a larger vehicle.
Phase Field is also used in Global Conquest as a global support power, though it requires a Threshold Tower before it can be used in the globe. Also, it has a stronger effect than the typical Phase Field, as it is able to affect entire armies/bases.