Psionovore

 were a race which thrive on the collective fear of others, often putting their potential prey into situations where they would be vulnerable to mental attack. The Doctor battled the Psionovores twice in his eighth and Nth incarnations, once in the Hellfire club and once in the Cloud of Fear. They have been shown to use personal fears that the prey possesses rather than an overall blanket form of intimidation. ''

Trivia
The Psionovores were first created for the Audio Visual play, Cloud of Fear by Alan W. Lear. In this and his later scripts ( Minuet in Hell, Enclave Irrelative and Planet of Lies) Lear concentrated on the darker side of Doctor Who, exposing the character in a vulnerable light. This proved extremely popular with listeners, making stories scripted by Lear among the most popular of the series.