The Somnivores are an alien race who, as their name would imply, feed on "somnatic" energy, also called dream energy. While there are many different lifeforms in the universe that are classified as somnivores, including some Earth animals and plants, the alien race referred to as the Somnivores are more aggressive, attempting on at least two occasions to colonize the Earth and turn its inhabitants into dream batteries.
History[]
The First Doctor had an undocumented encounter with the Somnivores. (Lethargica)
A group of Somnivores were encountered by the Doctor who found them in the silent ward of hospital in 1918 Toronto, Canada were they were found to be responsible for the Sleeping Sickness. (Lethargica)
Another group of benevolent Somnivores had been living as cats in Disneyland, CA where they fed on the joy and emotion generated by the park's attendees and used their abilities to close space-time rifts that opened periodically throughout the park, the result of a prior temporal incursion by the Time Lords. They performed this task as part of an arrangement with "the mustache man". (Roman Holiday, The Game of Classilon: Jinkies & Zoinks)
Non-canonical appearances[]
The Somnivores were encountered by the First Doctor along with companions Nardole, Turlough and Captain Jack Harkness, who had been abducted and placed into the Somnivores' dream engine. They managed to escape and prevent the Somnivores from placing humanity in the engine, effectively stopping the conquest and colonization of Earth. (Gallifrey One 2018 Live Show)
Behind the Scenes[]
The Somnivores were the first original alien to appear in any form of The Game of Rassilon, and are one of only four enemies aliens (along with the Daleks, the Weeping Angels and the Master) to appear in the live show and the podcast.
Lethargica alludes to a previous encounter with the Somnivores featuring the First Doctor. This is likely a reference to the aforementioned live show, however the podcast production team has stated that Gallifrey One live shows are non-canonical.