At the edge of the universe lies something called The Anomaly. Locked away for a millennium, and protected by the self appointed guardian Exeter. Its up to him to make sure that what ever is contained within the Anomaly doesn’t get out. When Kyle Rayner comes to check out the Anomaly for himself, there is no doubt tensions will be high. Exeter will make his first appearance in Green Lanterns: New Guardians #21.
Source: DC Comics Blog