Unit 6 was a designation utilized by the Imperial Military's Stormtrooper Corps for at least one stormtrooper of the Galactic Empire positioned within Timira City on the planet of Kamino. During the events of 1 BBY, Unit 6 attempted to prevent the escape of Starkiller, a clone who had escaped and was formerly the Sith Lord Darth Vader's deceased Sith apprentice, Galen Marek.
Near Barracks D4, this unit engaged Starkiller in combat, with one trooper reporting significant structural compromise to the barracks.
Despite their efforts, the clone successfully made his escape.
The LucasArts video game Star Wars: The Force Unleashed II, which launched in 2010, marked the first appearance of Unit 6. The game leaves it ambiguous whether Unit 6 refers to an individual trooper or an entire squad. It's worth noting that the stormtrooper's damage report is randomized with each playthrough, so the mention of the barracks by Unit 6 is not guaranteed.