Siege of Lasan The Siege of Lasan saw the near - extinction of the Lasat species under the military forces of the Galactic Empire . During the early years of the Empire , the Imperial Military brutally suppressed an uprising on the Lasat homeworld of Lasan . The conflict led to the near - extinction of the Lasat people and caused the Imperial Senate to ban T - 7 ion disruptor rifle s . Some Lasat survived , like Garazeb Orrelios , who later joined the rebellion , while others like Gron and Chava resettled on the mystical Lasat refuge of Lira San . Prelude . The Lasat species originated on the remote planet of Lira San in Wild Space . At some unknown point , a large number of Lasat colonized the planet Lasan and eventually lost contact with their kin on Lira San . The Lasat on Lasan established a royal family and came to regard Lasan as their species ' homeworld . Following the end of the Clone Wars , the Galactic Republic was transformed into the Galactic Empire . When the Lasat challenged the Empire , Imperial forces invaded their adopted homeworld , beginning the Siege of Lasan . History . Following an uprising on the species ' homeworld of Lasan , Agent Kallus of the Imperial Security Bureau was tasked with wiping out the rebellion . It was he who ordered the Imperial soldiers to use T - 7 ion disruptor rifle s against the Lasat civilians as a show of Imperial might . After defeating a member of the Lasan High Honor Guard , the guard then gave him his J - 19 bo - rifle in accordance with the Boosahn Keeraw , the Lasat warrior way . A number of Wookiee soldiers armed with weapons whittled from the wroshyr tree s of their home planet also took part in the battle , sacrificing their own lives to try to prevent the massacres on Lasan . Thanks to the Wookiees ' intervention , some Lasat were saved . Among the Lasat who survived were Garazeb Orrelios , a captain in the Lasan High Honor Guard , and his grandmother . During the battle , Zeb was tasked with protecting the royal family and Lasat . However , he was knocked out by an explosion . When he awoke , Zeb found that everything had been destroyed and blamed himself for failing to carry out his duty . Zeb was haunted by his experiences during the Fall and harbored a deep hatred for the Empire . Those Lasat survivors who were captured by the Empire ended up in prison camps . Aftermath . The Siege of Lasan ended with the devastation of the planet and the near - extinction of the Lasat species . As a result of the atrocity , the Imperial Senate banned the use of the T - 7 disruptors and the rifles were recalled and destroyed . The atrocity ' s evidence was seen by Taris ' s senator Tynnra Pamlo . However , copies of the T - 7 schematics escaped deletion and private weapons manufacturers continued to produce batches found on the black market . The Empire secretly planned to acquire some of this stock to restart production of them on Lothal . However , their plan was disrupted by the Spectres and R2 - D2 who destroyed half of the ion disruptors and sold the rest to the crime lord Cikatro Vizago . During the skirmish , Kallus personally fought Zeb and taunted the Lasat about his role in the fall of Lasan . Three years before the Battle of Yavin , the Spectres helped two other Lasat refugees , the former Honor Guard Gron and the mystic Chava , to rediscover the planet Lira San . During the journey , Gron contended that Lasan had not been destroyed but had been merely transformed in order to fulfill an ancient Lasat prophecy around Lira San . This prophecy held that Lira San could only be found if a " child of Lasan " saved the fool and the warrior from destruction . Following the rediscovery of Lira San , the rebels designated the planet as a sanctuary for other Lasat refugees . Later , the fall of Lasan became a subject of conversation between Zeb and Agent Kallus . The two adversaries had become stranded on the ice moon of Bahryn following an Imperial ambush above Geonosis . After Kallus recounted how he had obtained his bo - rifle from a fallen Lasat warrior , Kallus confided that he had not expected the Empire to unleash a massacre on Lasan and stressed that this was nothing personal . He also admitted that despite having taken credit for the use of the T - 7 ion disruptor rifle s , their use had not really been his idea . Zeb reassured his adversary that he had made peace with the past already . As a gesture of reconciliation , Zeb presented Kallus with a Bahryn meteorite as a parting gift . Behind the scenes . The Siege of Lasan was first briefly alluded to in the television movie " " , which first premiered on Disney XD on September 26 , 2014 . It was first mentioned in the first " Star Wars Rebels " episode " Droids in Distress " , which premiered on October 3 , 2014 . The fall of Lasan was further explored in subsequent " Star Wars Rebels " episodes including " Legends of the Lasat " and " The Honorable Ones " , which explores Garazeb Orrelios ' character and origins story in further detail .