Z-N0 was a J9 worker drone assigned to the Jedi investigator Ambaln by the Jedi Council. When Ambaln turned to the dark side, Z-N0 remained loyal to the Jedi Council. Although Ambaln's behavior made Z-N0 suspicious, Z-N0 did not realize Ambaln had betrayed the Council. Ambaln duped Z-N0 into leading a team sent by the Council into a trap on Lobaoc, during which Z-N0 fell into the marsh. The Jedi later retrieved Z-N0 from the marsh, and Z-N0 was assigned by the Jedi High Council to help track down Ambaln.