Trix is a Guster and a member of the Neverseen. He keeps himself hidden in a Neverseen cloak and was one of Wylie's kidnappers in Lodestar. His real name has not been revealed yet. He commonly works with Umber as mentioned in the book Lodestar by Keefe. After the events in Book 7: Flashback, Trix may play a bigger role in the Neverseen.
Identity Theories Edit
Another theory is that Trix is Marella's Dad, being one of the only known Gusters in the series. Fintan describes Marella as "the new recruit", so her manifestation must have leaked to him, which Trix/Marella's Dad would be able to do.