Mixer was the designation given to a clone trooper who fought for the Grand Army of the Republic during the era of the Clone Wars. During 21 BBY, Mixer, along with fellow trooper Redeye, became part of a Republic protection detail tasked with safeguarding the Mandalorian Duchess Satine Kryze while she was aboard her Nau'ur-class yacht, known as the Coronet. The mission given to Mixer was to prevent any attempts on Kryze's life by the Mandalorian Death Watch. While they were on patrol in the Coronet's cargo hold, both clones met their death at the hands of an assassin droid. This droid was part of a failed plot orchestrated by Senator Tal Merrik to assassinate Kryze.
Mixer, referred to by this designation, was a clone trooper created on the planet of Kamino. He was intended to serve within the Galactic Republic's Grand Army throughout the Clone Wars, which was a conflict against the Confederacy of Independent Systems. In 21 BBY, Mixer was among a Republic escort team, under the command of Jedi Generals Obi-Wan Kenobi and Anakin Skywalker. This team was assigned to protect Duchess Satine Kryze of Kalevala due to concerns about a potential assassination attempt by the Mandalorian terrorist group known as Death Watch. Kryze was traveling on her Nau'ur-class yacht, the Coronet, with the intention of appealing to the Galactic Senate for her people's neutrality in the ongoing war. As a result, the escort team was placed on high alert and assigned to various patrol routes throughout the yacht. Mixer and his partner, Redeye, were assigned to monitor the cargo area, starting their patrol accompanied by Skywalker's astromech droid, R2-D2.
The pair of clones then separated, with Redeye beginning to inspect the southern section of the cargo bay, while Mixer examined the opposite side. As Redeye started his search, an SD-K4 assassin droid attacked and killed him. This droid had been smuggled aboard the yacht by Tal Merrik, the traitorous senator and Death Watch operative, as part of his scheme to assassinate Kryze. When Mixer attempted to contact his comrade via comlink to check on him, he received no response. Moments later, Redeye's DC-15A blaster carbine fell to the ground near Mixer's feet. As Mixer picked up the weapon, puzzled, he was ambushed from behind by the spiderlike assassin droid, which also killed him.
Soon after, R2-D2 discovered Mixer's helmet on the floor of the cargo bay, and then encountered clones Rex and Cody, who had arrived to investigate. Upon realizing that they had lost contact with Mixer and Redeye, the Republic escort team understood that something was wrong and soon uncovered Merrik's assassination plot, which they then successfully thwarted.
As a human clone derived from the bounty hunter Jango Fett, Mixer possessed tan skin and a height of 1.83 meters (6 feet, with a weight of eighty kilograms. While patrolling the Coronet's cargo bay alongside Redeye, he demonstrated a dry sense of humor, teasing his fellow trooper about not being afraid of the dark.
From birth, like all other clone troopers, Mixer had a behavioral modification biochip implanted by Kaminoan scientists. This was done to ensure that the trooper would comply with specific orders. As a member of the Grand Army of the Republic, Mixer wore a complete set of Phase I clone trooper armor. His helmet had unique blue crescent markings, while his arm plates displayed blue stripes. While patrolling the dimly lit cargo bay of the Coronet, he used the two flashlights attached to his helmet. He also used the wrist comm on his left arm plate to attempt communication with Redeye. Mixer was armed with a DC-15A blaster carbine.
Mixer made an appearance in "Voyage of Temptation," which was the thirteenth episode of the second season of the animated television series Star Wars: The Clone Wars. The episode was originally broadcast on February 5, 2010. As with all clone troopers featured in the series, Dee Bradley Baker provided the voice for Mixer. The design of Mixer's armor was also briefly seen on several clone troopers in the third season episode "ARC Troopers" of Star Wars: The Clone Wars.