Self - Propelled Heavy Artillery Turbolaser The Self - Propelled Heavy Artillery Turbolaser ( SPHA - T ) , also known as the Self - Propelled Heavy Artillery ( SPHA ) , was a 12 - legged gun platform manufactured by Rothana Heavy Engineering . They were the largest ground based weapons used by the Grand Army of the Republic in the Clone Wars . During the Imperial Era , SPHA - Ts were used by the Imperial Artillery Corps of the Galactic Empire . Characteristics . Combining the devastating firepower of a permanent laser cannon emplacement with the ability to liberally walk into battle on powerful articulated legs , the Self - Propelled Heavy Artillery Turbolaser ( SPHA - T ) , also known as the Self - Propelled Heavy Artillery ( SPHA ) , was the largest ground based weapons in the arsenal of the Grand Army of the Republic at 140 . 2 meter s in length . It only used its twelve legs when maneuvering between firing positions ; when attacking an enemy target , a SPHA - T remained motionless to give its gunner s added precision for aiming its extraordinarily heavy turbolaser beam . Although it took no less than 30 specialized clone trooper s to man each gun platform , they were powerful and effective enough to blast through starship shields and hulls . However , SPHA - Ts could only be charged up to a certain level . History . Manufactured by Rothana Heavy Engineering , 100 SPHA - Ts were deployed in key positions on several battlefronts during the Battle of Geonosis , the opening battle of the Clone Wars . They were deployed in squad s of four at the rear of advancing All Terrain Tactical Enforcer s , while Low Altitude Assault Transport / carrier s ensured they were well defended by AT - TEs and infantry on foot , who were mobilized around and in front of SPHA - Ts to a distance of several kilometer s . SPHA - Ts provided an impregnable line of defense for the fleet of " Acclamator " - class transgalactic military assault ships that landed immediately outside the Petranaki arena , which supplied an assembly point for the deadly juggernauts . During the battle , they proved particularly effective on the battlefield commanded by Jedi Master Yoda , who ordered a squad of SPHA - Ts to focus fire upon a fleeing core ship ; this caused antigrav repulsorlift malfunctions that grated a tractor beam effect with the ground , greatly accelerating its fall and destroying the ship . However , after these shots , the SPHA - Ts had to be replaced with charged guns from the rear lines . After the Clone Wars and the rise of the Galactic Empire , the Imperial Army ' s Imperial Artillery Corps used the SPHA - Ts as mobile artillery . Behind the scenes . Originally created for the 2002 film , the Self - Propelled Heavy Artillery was designed in concept sketches by Concept Design Supervisor Erik Tiemens . His initial concepts had the self - propelled cannon be mounted on treads , but George Lucas instead suggested that it be a walker like its AT - TE cousin . During production , the SPHA - T was called " Clone Tank A . " An early animatic featured SPHA - Ts being deployed from " Acclamator " - class assault ships on Geonosis , though this scene was cut from the final film . The RX - 200 " Falchion " - class assault tank featured in " The Zillo Beast " and " The Zillo Beast Strikes Back " was redesigned from the SPHA - T to better resemble the maser tanks from the " " franchise .