Planet Prison The Planet Prison was a superweapon developed by the Galactic Republic during the Cold War with the Sith Empire . Created by Doctor Nasan Godera and weaponized by a team of scientists under the leadership of Doctor Tarnis — in actuality a Sith Lord and the son of the notorious Darth Angral — the weapon was intended as a way to peacefully blockade a planet . When the project ' s prototype neared completion , Tarnis attempted to steal the device and use it on the Republic capital world of Coruscant through an elaborate ruse with the help of the Migrant Merchants ' Guild and Black Sun criminal organizations . However , Tarnis was killed in the ruins of the Jedi Temple by a young Jedi Knight , and the device was destroyed before it could be fired . The technology would be later combined with several other weapons by Darth Angral into the ship - mounted Desolator superweapon , which the Sith Lord used to devastate the planet Uphrades , although the Jedi Knight defeated Angral aboard his warship above Tython just before the ship was destroyed by Republic fighters . Description . The Planet Prison was designed to supercharge the upper atmosphere of a planet with what was essentially an ion pulse , turning the entire atmosphere into an enormous ion cannon . Any vessels that attempted to enter the atmosphere , whether they be leaving the planet or attempting to land , would be instantly disabled . The engines and systems of any vessel in the ion field would shut down , forcing the ship to crash . However , one drawback of the weapon was that it required an immense amount of energy and time to charge up to firing capacity , and it generated large amounts of heat while charging . History . Origins . The Planet Prison project was first conceived by the Mon Calamari General Var Suthra , who witnessed the devastation of the Sacking of Coruscant by the Sith Empire in 3653 BBY and saw the fall of the Jedi Temple . The brilliant scientist Doctor Nasan Godera had left the Galactic Republic ' s employ in disgust after the Treaty of Coruscant ended the Great Galactic War and began a tense Cold War between the two powers , and Suthra was left with several new technologies still in the design stage . Seeing a purpose for these technologies , Suthra started several projects to weaponize the ideas , as a way of honoring the Jedi who had been killed in the attack by ensuring that the next war ended quickly . The different weapons projects eventually came to be headed by Doctor Eli Tarnis , though he worked mainly on the Planet Prison . However , Tarnis was in fact the son of Darth Angral , the commander of the Sith forces who had led the Sacking of Coruscant . A Sith Lord himself , Tarnis was masquerading as a scientist to gather information on the weapon projects . Tarnis headed a five - man design team for the Planet Prison , including a man named Jonkan . Deception and destruction . In 3643 BBY , the project was nearing completion , and the scientists were about to begin field testing when Tarnis hired the Black Sun criminal syndicate to steal the design files . Black Sun tasked a Rodian named Vistis Garn with the job , and Garn proposed the heist as his own idea to his main employers in the Migrant Merchants ' Guild , a rival criminal gang . Garn and his team infiltrated a military warehouse and stole the files from the building ' s computer system . They also made off with a shipment high - tech weapons and munitions , but not before Garn was identified by the building ' s security system . General Suthra and Jedi Masters Bela Kiwiiks and Orgus Din assigned Din ' s former apprentice , a Jedi Knight , the task of recovering the files , and ordered Kiwiik ' s Padawan Kira Carsen and the SIS Agent Galen to assist the Knight . The Knight and the astromech droid T7 - O1 raided the warehouse to where Garn had retreated , and recovered the files and weapons . However , while the Knight was in the Old Galactic Market on the mission , Tarnis arranged for his own " kidnapping " by the Black Sun , right under the noses of the SIS and the Coruscant Security Force in the Senate Tower . The Knight and T7 - O1 intercepted the kidnappers at the nearby spaceport and eliminated the Black Sun criminals with the help of Carsen and the Coruscant Security Force . Defeating the Black Sun ' s leader , Zeer , the trio learned that Tarnis had been taken to Black Sun territory . Traveling to the gang - controlled region , the Knight and T7 - O1 learned of Tarnis ' true identity as a Sith Lord , and pursued the traitor to the Justicars ' Sector in an attempt to locate the Planet Prison device . There , the duo found the bodies of the project scientists , who had been tricked into bringing Tarnis the actual prototype . One of the scientists , Jonkan , was able to tell the Knight that the weapon needed time to charge and that it generated massive amounts of heat while doing so . Using that information , the Knight and Carsen were able to locate the Planet Prison in the ruins of the Jedi Temple , and pursued Tarnis there . Standing before holograms of Tarnis ' father and Angral ' s apprentices , the Knight fought and defeated Tarnis and destroyed the Planet Prison device . Legacy . The Planet Prison technology would later be reused by Tarnis ' father Darth Angral , who combined it with several other stolen superweapons to create the Desolator weapon . Angral installed the device on his personal flagship , the " Oppressor " , and used the Desolator to devastate the Republic agriworld of Uphrades . The ionization of the planet ' s atmosphere worked perfectly , preventing any survivors from escaping the planet , and the crew of the Republic medical frigate " Daybreaker " intentionally allowed their ship to be disabled by the field so that they could aid the survivors . Having successfully tested the weapon , Angral moved his ship to the Jedi Order ' s homeworld of Tython and prepared to use it in his quest for revenge against the Knight for the death of his son . Above Tython , Angral deployed micro - burst versions of the Planet Prison , temporarily ionizing the planet ' s atmosphere and disabling the Republic fighters mobilized against the " Oppressor " . However , the Desolator also inherited the Planet Prison ' s power drawbacks , requiring the weapon to charge for extended periods of time . That weakness enabled the Knight , T7 - O1 , and Carsen to slip aboard the " Oppressor " and disable the Desolator before it could fire again . With the destruction of the " Oppressor " by Republic fighters , the last traces of the Planet Prison technology were finally eliminated . Behind the scenes . The Planet Prison was created for " " , a released by BioWare on December 20 , 2011 . It serves as the target of the Jedi Knight class storyline on Coruscant , and is the first of several superweapons that serve to further the plot of the Act I storyline . Regardless of alignment choices , the Planet Prison is destroyed by the player after Tarnis is defeated . It is mentioned in the Act I finale by Doctor Nasan Godera while discussing the Desolator weapon , as Godera analyzes the superweapon ' s design to find a flaw similar to that of the Planet Prison . The Planet Prison is also mentioned in the 2012 reference guide " " , in the entries for Doctor Godera and the Jedi Knight class storyline .