All Terrain Ion Cannon The All Terrain Ion Cannon ( AT - IC ) was an uncommon variation of the All Terrain Armored Transport walker equipped with a massive ion cannon . Although ion cannons were rarely found aboard ground vehicles , the Galactic Empire converted a small number of its AT - AT fleet into mobile ion cannons . The Empire deployed the AT - IC for the mobile defense of strategic locations . Characteristics . The All Terrain Ion Cannon ( AT - IC ) was an uncommon variant of the standard All Terrain Armored Transport walker . The AT - IC resembled the standard AT - AT design , except half of its structural body space was dedicated to supporting a massive ion cannon . History . Ion cannons required a considerable power output , so they were rarely found aboard small ground vehicles , with some exceptions . During the Clone Wars , the Galactic Republic and Commerce Guild both employed vehicles equipped with light ion cannons as antiaircraft weapons : the Self - Propelled Heavy Artillery walker and the OG - 9 homing spider droid , respectively . Years later , the Galactic Empire converted a small number of its AT - AT walkers into mobile ion cannons , which became known as All Terrain Ion Cannon walkers . The Empire utilized the AT - ICs as mobile defense walkers for strategic Imperial locations . Behind the scenes . The All Terrain Ion Cannon was originally one of several vehicles planned for inclusion in Kenner ' s 1986 " The Epic Continues " toy line , an initiative to continue the success of the " Star Wars " franchise toy line following the 1983 theatrical release of . The Kenner design team developed a number of new vehicle model prototypes for " The Epic Continues " through a process , which involved taking pieces of existing toy models and combining them to create an entirely new model . For the AT - IC prototype , the Kenner designers took a full - size AT - AT toy model and replaced a large portion of its aft section with a rear - mounted ion cannon , calling it a " heavily armed A . T . A . T used exclusively for mobile defense of strategic Imperial locations . " However , Lucasfilm rejected Kenner ' s proposal for " The Epic Continues " , rendering the AT - IC outside the realm of " Star Wars " canon . Details of the AT - IC and the background story behind the failed " The Epic Continues " toy line were first revealed in the 1995 article " Tales of Phantom Toys " from " Star Wars Galaxy Magazine " 2 , written by Stephen J . Sansweet . The AT - IC first officially entered " Star Wars " canon through the 2004 reference book " The New Essential Guide to Weapons and Technology " , co - edited by Sansweet , which provided a brief mention of the AT - IC among other ground vehicles equipped with ion cannons . In 2008 , the AT - IC was provided an entry in " The Complete Star Wars Encyclopedia " , co - written by Sansweet , which included the Kenner design team ' s original description of the vehicle as a " mobile defense of strategic Imperial locations . " At present , photographs of one of Kenner ' s original presentation binders for " The Epic Continues " are hosted on The Star Wars Collectors Archive website , including a picture of the original All Terrain Ion Cannon prototype model . The website notes that the AT - IC prototype ' s ion cannon was recycled from Kenner ' s original Death Star playset . However , despite mentions in " Star Wars " reference material , no image of the AT - IC was ever officially included in " Star Wars " Legends .