An unmage uses unmagic to accomplish his goal. As unmagic is quite rare unmages are, too. An unmage was used by the Dihanurs in the fall of 1039 KF to commit the Rokat murders. In an AMA on reddit, Tamora Pierce revealed his name: "His name was Fareed. If he had a last name, he'd forgotten it, because he was sold to the crime family when his magic manifested itself."
The unmage is used by Alzena and Nurhar Dihanur to kill all Rokats in the Pebbled Sea due to the fact that one of their own kinsfolk was murdered and be-headed as a lesson not to mess with the Rokats. The unmage is only a child and is terribly thin and is addicted to dragonsalt.
He was originally captured by pirates, who cut off his legs, beat him, and used his unmagic to commit crimes. The Dihanurs rescued him and introduced him to dragonsalt so he would be easier to control.
The unmage was killed when Sandry was forced to spin the unmagic net to free Pasco Acalon from the Dihanurs. He had become so consumed by his unmagic that he didn't seem to register any pain, unlike the Dihanurs, who screamed in agony as their bodies ripped apart. It is likely most unmages will eventually be consumed by their power in the same manner, and thus, they likely have short lifespans.
Powers and abilities
The unmage uses unmagic which is a very rare version of magic. It is the absence of all things (light, sound, magic etc.) and can make people invisible and teleport. After teleporting in the unmagic portal with the Dihanurs he can no longer open such portals.