Q4P3 was a protocol droid who was once sent to Mustafar to retrieve the "Codex" for his master, Pann. While there, he spoke with several of the droids hoping to discern the location of the "Codex". One of the droids he spoke to led him to believe that he had found the "Codex", but he was not able to get to it due to the fierce animals on the planet. Instead, he waited inside the Mensix Mining Facility for someone he could hire to retrieve it.