This lego model is based off a combination of the 2020 ATAT, 2020 Death Star Tractor Beam, 2014 Death Star Troopers Battle Pack, and the design of the 1986 "The Epic Continues" Heavy ATAT toy prototype.

"The All Terrain Ion Cannon (AT-IC) was an uncommon variation of the All Terrain Armored Transportwalker equipped with a massive ion cannon. Although ion cannons were rarely found aboard ground vehicles, the Galactic Empire converted a small number of its All Terrain Armored Transport fleet into mobile ion cannons. The Empire deployed the All Terrain Ion Cannon for the mobile defense of strategic locations." -Wookipedia