Mox's story begins as a youthful clone apprentice who, in the aftermath of the Clone Wars, was captured by the forces of the Galactic Empire. Along with a group of other apprentices, Mox was removed from his home world, Kamino, and transported to an Imperial research facility managed by physician Royce Hemlock on Setron. It was there that samples of the clones' blood were extracted for the purpose of experimentation.
Following the Empire's loss of control over an experimental weapon, specifically a slither vine, at the facility, they abandoned the site and initiated an orbital strike to erase all traces of their activities. Mox, along with fellow clones Deke and Stak, managed to escape before the destruction occurred.
Mox's origin traces back to the bounty hunter Jango Fett, as he was created as a clone for the Grand Army of the Republic by the Kaminoans. He served as a clone apprentice until the emergence of the Galactic Empire. At that time, he and a number of other young clones were relocated to one of Hemlock's laboratories on the planet Setron. They were informed that they would receive additional training. However, the clones were instead subjected to blood sample collection for study and were held as prisoners by the Advanced Science Division under the direction of Doctor Royce Hemlock. Soon after, the Empire lost control of an experimental weapon, which led them to relocate and destroy the facility. Mox, along with two other apprentices, Stak and Deke, survived, but found themselves abandoned.
Sometime after the clones made their escape, they encountered Hunter and Wrecker from Clone Force 99 in the forest near their camp. Hunter and Wrecker had arrived on Setron in the hopes of locating Omega, who had been captured by the Empire. Initially, Mox was doubtful, wondering if Hunter and Wrecker were there to hunt them down. Hunter inquired if they could retrieve any data from the lab, and Deke mentioned that a control panel remained untouched by the slither vines. Mox advised against going, emphasizing the danger and toxicity of exploring the area. Despite Mox's concerns, Deke assisted Clone Force 99 in their endeavor to obtain data from the abandoned lab.
While Deke was away with Hunter and Wrecker, Stak approached Mox, suggesting that they should take Hunter and Wrecker's ship and flee the planet. Although Mox initially refused, expressing his respect for Hunter and Wrecker's dedication to their squad and his reluctance to abandon Deke, he reconsidered when Stak pointed out that the vines could destroy the ship, leaving them stranded. He instructed Stak to lead him to the ship, and he watched as Stak managed to hotwire it and gain entry. However, before they could decide to take the ship and leave, Deke called for their assistance over the comms. Mox and Stak decided to go and rescue them, piloting the Havoc Marauder over the lab to save them. The apprentices lowered cables for them to grab onto, but before Hunter and Wrecker could reach the ship, the slither vines attempted to pull the Marauder into its mouth. Deke threw a thermal detonator into the slither vine's mouth, but it proved insufficient. Wrecker instructed the apprentices to retrieve the entire box of detonators from the ship and throw them into the slither vine. Deke, now safely on board the ship, assisted Mox in grabbing the box and throwing it into the mouth of the slither vine. The detonators exploded, causing the slither vine to retreat, allowing Stak to pilot the Marauder to safety.
Having finally escaped their isolation on Setron, the three young clones were brought to Pabu for safety. They later enjoyed ice cones there. After CX-2 destroyed the Marauder, Hunter tasked Mox and Stak with escorting Wrecker to Shep's residence for treatment, while Deke was instructed to get AZI-3 to address Wrecker's injuries.
Mox made his debut in the second episode of The Bad Batch Season 3, titled "Paths Unknown." His voice was provided by Daniel Logan, who portrayed young Boba Fett in Star Wars: Episode II Attack of the Clones and voiced the same character and many clone cadets in Star Wars: The Clone Wars.