The Trigannons are a spacefaring race of three-feet-tall, tailed, imp-like humanoids from the Spulion System.
They have based their entire technological development on the use of psionic energy, which is emanated by their own minds and controlled and augmented by psychoactive minerals found on their own homeworld. In other words, their technology consists basically of stones, which can enable them to perform numerous psychic feats, including telepathy, telekinesis and teleportation. They are also able to assume an illusory appearance and to project illusions which can actually interact with the world; so that a telepathic projection of them can be almost as deadly as the real thing. One ability that they lack, though, is that of hypnotizing or controlling minds.
Trigannons live for hundreds of thousands of years, and seem to have a special bond with their technology, particularly their ships. This is due to the unusual nature of their technology, which is deeply dependent on individual brain patterns to work. The crew bonds with their own vessel for life and individuals cannot be replaced.
- Doctor Who audio stories - The Spectre of Lanyon Moor (2000)