Zuckuss was an insectoid male Gand findsman who worked as a bounty hunter prior to and during the Galactic Civil War. A skilled tracker who often worked with 4-LOM, Zuckuss had a run-in with Han Solo that left his ship, the Mist Hunter, powered down on a strange planet. He was later among the hunters assembled by Darth Vader to find the Millennium Falcon following the Battle of Hoth, although Boba Fett ultimately earned the bounty by delivering Solo to Jabba Desilijic Tiure.
After losing the carbonite frozen body Han Solo to Qi’ra and Crimson Dawn directly after the events of the Empire, a monstrous bounty was placed on Boba Fett’s head by Jabba the Hutt. As a result of this, his old friends Beilert Valance and Dengar set out to find him before other bounty hunters could get their hands on him.
As part of this search they travelled to the planet Gand, which is the homeworld of Zuckuss to recruit him as part of the team. Once they found him, they were shocked to see he had shut himself off from all outside contact because he was betrayed by his life long friend 4-LOM, who tried to murder him. Dengar and Valance didn’t have much time to console him because the ammonia rich atmosphere of his planet was eating through their suits, and he simply told them that now they know the pain he suffers when he has to breath their cured air… But finally, he says that pain is nothing compared to being left for dead and betrayed by his best friend.
After many tears, Zuckuss eventually is snapped out of it and offers to help find Boba Fett and get the frozen body of Han Solo back.