Interdiction field / Legends An interdiction field was an artificial gravity well that disabled hyperspace capability in most starships . It was used to prevent ships from entering hyperspace as well as draw ships out of hyperspace and into realspace . History . Zabrak engineers developed the interdiction technology during the Mandalorian Wars . Soon the Galactic Republic ordered " Interdictor " - class star cruisers that used powerful tractor beams to produce an interdiction field . The most notable of those vessels was the " Leviathan " . However , this form of " interdiction " did not produce large amounts of gravity , and was largely ineffective on the hyperspace engines of later years . During that same time period , the Mass Shadow Generator superweapon may have been an example of an interdiction field generator that rivaled the ones built by the Empire years later . It required tremendous power which requirements could only be met by using the abnormally powerful gravity wells around the Malachor system . It used a huge burst of gravity to crush ships and much more dangerously — whole planets . Advances and countermeasures were researched , soon the Mandalorian Wars ' interdictors became useless against new hyperdrive sensors and multiphase null field units . A millennium later , the problem of power consumption still made interdiction field generators capable of disrupting modern hyperdrives unpractical . While the theory behind it was well known , movable objects , such as ships , had a difficult time producing enough power to create the mass shadows . The Vagaari ship nets seemed to have found a way around the power consumption problem . It is unknown whether this technology was created by the Vagaari or stolen from another race in the Unknown Regions , like most of their other technology . Thrawn stole a " ship net " from the Vagaari while he was a commander in the Chiss Expansionary Defense Fleet . He used this gravity projector successfully in several engagements . The Interdictor technology used on his ships while a Grand Admiral in the Galactic Empire was probably developed separately by the Empire or late Republic — several years after the supposedly " primitive " races in the Unknown Regions . The Clone Wars allowed the Republic to fund new research and The Empire benefited from these technological advances . The Galactic Empire used the Detainer CC - 2200 Interdictor Cruiser , Immobilizer 418 cruiser and Dominator Star Destroyer specifically for hyperspace immobilization . The " Sovereign " - class Super Star Destroyer and the " Eclipse " - class dreadnought also had gravity well generators , preventing targeted vessels from escaping their firepower . Yuuzhan Vong dovin basal s were also able to project gravity wells to drag their ships through the interstellar void . When these organisms concentrated their energy wells , they could create massive gravitational anomalies , such as causing a space station to collapse or a moon to collide with its orbital partner , a tactic known as Yo ' gand ' s Core . The Yuuzhan Vong interdictor cruiser - analogue was the Vua ' spar interdictor . Furthermore , the technology was often put to use by pirates in order to pull vulnerable cruisers out of hyperspace in order to be boarded . It was used by the Republic in the opposite way — intercepting pirate ships before they could escape . As with any tactical weapon , innovation created a new technology to void its capabilities . The Bakuran s ' HIMS generators were capable of nullifying the containment capabilities of interdiction fields . These HIMS generators were fitted onto the vessels of the Bakuran Defense Fleet which consisted of three " Bakura " - class Destroyers " Watchkeeper " , " Defender " and " Sentinel " , and the " Namana " - class Light Cruiser " Intruder " . These starships played an important role during the Battle of Centerpoint Station though half of the fleet was destroyed .