The way the Ratchet & Clank wiki capitalizes words has changed; therefore, this article should be checked, and, if necessary, capitalization should be fixed.
Grays were beings encountered in on the Damosel Moon, Lunar City, as they invaded it. They piloted a Mothership that spawned dozens of Robot Aliens, also controlled by Grays, to take over the moon. Ratchet and Giant Clank destroyed hordes of Robot Walkers and the Mothership, ending the invasion of Lunar City. In the class domes of the vehicles you can just barely make them out.