Wutzek
From Wookieepedia, the Star Wars wiki.
Wutzek was the last known Force Demon. It was imprisoned for a time by an evil cult called The Five, only to be set free sometime after the Battle of Yavin by Chewbacca, who along with Han Solo and Leia Organa, had also been captured by The Five. It defeated the cult and allowed the Rebels to go free, though Wutzek, a being of immeasurable power, was now also free to roam about the galaxy unchecked. Its further activities are unknown.
