The All Terrain Armored Cannon (AT-AC) represented a bipedal walker utilized by the ground forces of the Galactic Empire in the early years of the Imperial Era. This walker belonged to the all-terrain vehicle family and served as an initial design for walkers intended for urban control, ultimately influencing the later creation of the All Terrain Scout Transport.
The AT-AC, short for All Terrain Armored Cannon, was a walker type of all-terrain vehicle manufactured by Kuat Drive Yards. It saw service with the Galactic Empire during the beginning of the Imperial Era, or early days. Moreover, this walker was an early design in the urban suppression walker series, acting as an important developmental stage leading to the All Terrain Scout Transport within the all-terrain line. The AT-AC was equipped with a pair of chin-mounted cannons, a heavily armored cockpit, a narrow viewport, and two large windows containing dual blaster barrels.
Around 18 BBY, the Imperial Advanced Science Division deployed a number of AT-ACs on the planet Ord Mantell during a raid aimed at capturing Omega, the renegade clone from Clone Force 99. As Imperial units occupied the streets of Ord Mantell City, the AT-ACs assisted in enforcing Imperial authority by parading through the city's thoroughfares. While patrolling near Cid's Parlor where Imperial clone commandos were conducting their raid, one of these walkers was commandeered by Echo and AZI-3. Echo employed the stolen walker to attack a Low Altitude Assault Transport that was preparing to transport his captured squadmates off-world. In response, another AT-AC destroyed the hijacked walker by targeting its inverted knee joint, which caused it to collapse. The AT-AC continued its assault on the Bad Batch as the rogue clones escaped the area.