In 3996 BBY, amidst the chaos of the Great Sith War, a significant battle unfolded within the Senate Hall of the Galactic Republic. This confrontation pitted Vodo-Siosk Baas, a Krevaaki Jedi Master, against Exar Kun, his former padawan who had embraced the dark side to become a Dark Lord of the Sith. The clash began on Coruscant, specifically within the Grand Convocation Chamber of the Senate Hall, during the trial of Kun's own Sith apprentice and fellow Sith Lord, Ulic Qel-Droma. Accompanied by Mandalore the Indomitable, Exar Kun made his dramatic entrance into the Senate Hall on Coruscant, interrupting the proceedings against Ulic Qel-Droma, who was being judged for his offenses against the Republic. Employing Sith sorcery, the Dark Lord froze the minds of the assembled Galactic Senate, leaving only the Jedi present and the Supreme Chancellor unaffected. After liberating Qel-Droma, he proceeded to assault and murder the Chancellor before attempting to leave; however, their path was blocked by the arrival of Kun's old mentor, Jedi Master Vodo-Siosk Baas.
A fierce exchange of words erupted between Kun and Master Baas, with neither willing to concede to the other's demands. Kun then activated his lightsaber and issued his challenge, his blade clashing against Baas' Force-imbued quarterstaff in combat. Recognizing that they were evenly matched, Kun sought to gain an advantage by revealing his latest weapon, an ancient Sith design: the double-bladed lightsaber. Overwhelmed by the power of Kun's attacks, Baas foresaw his impending death and prophesied a future encounter where he vowed to defeat Kun once and for all. He then became one with the Force, falling to Kun's killing blow, and was mocked by his former apprentice even as he died. With his role in the bloody Sith rebellion complete, the Dark Lord of the Sith departed the Convocation Chamber with Ulic Qel-Droma and Mandalore the Indomitable, resuming their pursuit of galactic domination.
The galaxy's Great Sith War was a period of great upheaval for both the Jedi Order and the Galactic Republic. In just over a year, the Brotherhood of the Sith, under the leadership of Dark Lord Exar Kun, had consistently outmaneuvered the Jedi and the Republic in battle. Kun's next objective was to eliminate the Jedi leadership, tasking his newly-initiated Sith converts with assassinating their Masters, a plan that was to culminate in the death of Kun's own Master, Vodo-Siosk Baas. The new Sith then departed Kun's stronghold on the jungle-moon of Yavin IV, just as Mandalore the Indomitable's starship landed, and the Mandalore rushed to speak with the Dark Lord. He explained that the premature attack on the galactic capital of Coruscant by Kun's fellow Sith Lord and Krath leader Ulic Qel-Droma, had failed. During the battle, Qel-Droma had been imprisoned in a wall of light-side energy by the Jedi, and taken into custody by the Supreme Chancellor of the Galactic Republic. The Chancellor was determined to have the fallen Jedi tried for his war crimes against the galaxy, believing that execution was the only fitting punishment for Qel-Droma.
Mandalore was determined to rescue the Krath warlord, and he sought Exar Kun's assistance to do so. However, the Dark Lord had previously warned Qel-Droma against a preemptive strike upon the galactic capital, and his capture only confirmed Kun's earlier concerns. Nevertheless, he agreed to help Mandalore, as Qel-Droma remained a crucial asset to their cause. They boarded Kun's vessel, Starstorm One, and set out to rescue their comrade from the clutches of the Galactic Republic.
Exar Kun and Mandalore the Indomitable, accompanied by a group of Sith Massassi warriors, stormed into the Galactic Senate Hall. In the center of the Convocation Chamber was Ulic Qel-Droma, in shackles and on trial before the entire Senate assembly, including the Supreme Chancellor of the Republic. Also present were Ulic's former allies: Jedi Knights Nomi Sunrider, Sylvar, and his brother, Cay Qel-Droma. Before the horrified Senate, the Dark Lord freed Qel-Droma from his shackles using the Force, and then used his Sith powers to mentally paralyze the entire audience, except for the Jedi and the Chancellor. Exar Kun then approached the podium in the center of the Chamber, but was attacked by the confused Chancellor, whose futile attempt to defend himself led Kun to plunge his fingers into the Chancellor's skull and lift him into the air, mentally forcing him to repeat Kun's words as if he were a puppet. The Chancellor echoed Kun's speech as he outlined his plans to restore the legendary Sith Empire, denouncing the Republic and declaring it obsolete in his grand scheme. Kun then dropped the dead Chancellor in a pool of his own blood before the captivated audience, and gathered the freed Qel-Droma, Mandalore, and his Massassi, intending to leave. However, the Sith were once again interrupted by the arrival of Kun's former teacher, Vodo-Siosk Baas.
The Cathar Jedi Sylvar attempted to battle Exar Kun in his place, but Master Baas stopped her, considering his former student his personal responsibility. Baas demanded that Exar Kun abandon his dark side practices, but Kun refused, instead tempting Master Baas with a position in the newly-formed Sith Brotherhood. However, when the Krevaaki Jedi declared that he would never submit to Sith teachings, Kun activated his lightsaber. With no other options, Baas readied his staff, and the battle commenced.
Exar Kun remembered his previous defeat against Baas' superior skill as he fought relentlessly with his blue blade; Baas, however, fought with his Force-imbued staff, ready to prove once again that it was more than a match for any lightsaber. Meanwhile, the Senate assembly remained entranced by Exar Kun's spell, and the Jedi were held back by Mandalore and Kun's Massassi warriors. Master Baas effortlessly held his own against the Dark Lord, ignoring all of Kun's taunts. Kun likewise refused Baas' pleas for surrender. Neither opponent yielded under the strength of the other's blows, and try as he might, Vodo-Siosk Baas was unable to defeat Exar Kun, nor could he convince him to renounce the dark side and end his campaign of galactic destruction.
Annoyed by the Jedi Master's persistent urging, Exar Kun decided to escalate the fight. To Baas' surprise, Kun twisted his lightsaber hilt and produced an identical blue blade from the opposite end: he now fought with a double-bladed lightsaber. Master Baas was unprepared for the unique weapon, and the Sith took full advantage, raining down blows upon him. Baas' defenses could no longer withstand the assault; thus, he knew that the duel was lost, and he submitted himself to the Force. He then told Exar Kun that he would one day defeat him, perhaps not now, but one day and forever. Ignoring this proclamation, Exar Kun bade his former Master farewell and brought the final blow down upon him, cleaving his staff in two. There on the Senate floor, Vodo-Siosk Baas became one with the Force. Only his Jedi robes and the splintered wood of his cane remained.
Dark Lord of the Sith Exar Kun and his apprentice Ulic Qel-Droma strode triumphantly from the Senate Chamber with Mandalore and Massassi warriors following close behind. The Sith bid the assembly farewell and departed for Yavin IV, leaving Nomi Sunrider, Cay Qel-Droma, and Sylvar to cradle the robes and broken staff of Vodo-Siosk Baas in grief.
Across the galaxy, Exar Kun's Sith servants were also attacking their respective Masters, striking them down to pave the way for the great Sith destiny foretold by Kun. With the threat of the Jedi Masters removed, the Brotherhood of the Sith resumed their campaign against the Republic, intending to crush it under the power of the dark side.
Vodo Siosk-Baas' final words to Exar Kun did come to pass many thousands of years in the future. At the new Jedi Praxeum established in the Massassi temple on Yavin IV by Jedi Master Luke Skywalker in 11 ABY, Kun's disembodied spirit began to harass Skywalker's Jedi trainees with temptations of the dark side. However, when the students joined forces to confront Kun, the ghost of Master Vodo-Siosk Baas appeared, and assisted the trainees in vanquishing Kun's spirit forever.
The duel in the Senate Hall was written and conceived by author Kevin J. Anderson for the fifth Tales of the Jedi story arc entitled The Sith War. First appearing in the comic issue The Trial of Ulic Qel-Droma of The Sith War arc, the duel marked the first death in Kun's Jedi "uprising" scheme. Anderson used the duel to both eliminate the character of Vodo-Siosk Baas and reunite the characters of Ulic Qel-Droma and Exar Kun, a union that began in the final issue of Anderson's Star Wars: Tales of the Jedi - Dark Lords of the Sith story arc, a joint project with fellow author Tom Veitch.
The Complete Star Wars Encyclopedia mistakenly places Vodo-Siosk Baas's death at the hands of Exar Kun as during the Conclave on Deneba. However, there are entries that correctly state that it took place on Coruscant.