Pranavore

Pranavores were a gestalt species native to Earth that magnified empathic fields and fed on excess positive human emotions. They were harmless beings and naked to the human eye, as they lived on the Psychosphere, Earth's psychic dimension. They worked on a hive mind, in search of sites of high positive emotions.

The Tenth Doctor stated he only recently found out about Pranavores and knew little about them. After altering the damaged ocular circuits on a special helmet, he allowed Gabby Gonzalez the opportunity to view the Pranavores, who Gabby thought looked beautiful. A species known as the Fleshkind experimented with some of them in the hopes of creating a psychic weapon, separating them from their hive mind. Without it, they mutated and became into the Cerebravores, attacking and killing all of them, eventually finding the way to break out of the Psychosphere. (COMIC: Revolutions of Terror)