Name: Mystan Benekasbeel
Species: Psion Lunatak
Family: Uncle to Zanaya
Powers: Powerful telekinetic, mild telepathy
Mystan is one of the high priests of the Psion temple. There are nine in all and he's one of the youngest. He's also the one most likely to be sent on errands abroad.
When performing mental abilities, emotions can be both a hindrance and a benefit. A telekinetic might have an easier time lifting a heavy object if a loved one is pinned under it, but concern for the loved one might lead them to faltering in lifting an unrelated object. To this end, Mystan is of the belief that it's easier to be emotionless than to be hurt by one's own emotions, and it's a lesson he pushes on his students.
He has slipped, though. During the private war between himself, Lura, and Zanaya against Knave, emotions got the better of all three. It was an embarrassing situation that nearly sparked a war between the Thundercats and Lunataks. Mystan was stripped of his powers as a consequence, and forced to decide between his pupil and his niece. His emotionless aura returned and he slew Zanaya.
What effect his punishment will have on his status within the temple remains to be seen, but one can assume that Mystan will find a way to recover.