Shadow Ring is an Epsilon support power available from the Pandora Hub, which makes friendly units in the target area cloaked for a period of time. It is especially useful to get the proselyte's troops safely through strong enemies – as long as there are no detectors in range.
The AI will use Shadow Ring at the center of their own base (near their Construction Yard), which is usually unreliable at times.
The Shadow Ring is first usable in the campaign in Human Shield. In this mission as well as in Huehuecoyotl, Blood Rage, Survivors and Backbitten (2nd player only) (does not apply to Survivors on Mental difficulty), Shadow Ring can be activated without the need of a Pandora Hub, as the player doesn't have access to bases.
The Shadow Ring can cloak a maximum of 29 vehicles at one time.