TB-3 served as a protocol droid on the remote planet of Parnassos. He was positioned at Terpsichore Station, which was a mining operation run by the Con Star Mining Corporation. After Phasma, Brendol Hux, and their troops became gravely ill, he was instrumental in guiding them to safety. He guided them through a concealed entrance beneath the sand into the facility, and then showed them the location of the medbay for Hux's treatment. Subsequently, he escorted the party to handle the payment arrangements. In an opulent chamber, they were offered refreshments and food, which the local Scyre people thought was both fascinating and bizarre, having never encountered such items. Following this, TB-3 inquired about their intended method of payment. Due to their inability to pay, they were compelled to work as laborers to ensure Hux's survival.