The Duel in the Senate was a vicious battle fought between the Dark Lord of the Sith, Darth Sidious, and the Jedi Grand Master Yoda. The battle took place in the Senate Building on Coruscant, in 19 BBY, shortly after Yoda survived an attempt made on his life during Order 66. Throughout the confrontation, the two masters of the Force engaged in deadly lightsaber combat, with each making liberal use of their Force powers; which resulted in considerable damage to the Grand Convocation Chamber.
Though the pair seemed evenly matched, the duel concluded when Sidious managed to gain the higher ground, meaning that Yoda would be at too great a disadvantage to continue pressing the attack. Having failed, the Jedi Grand Master retreated into exile, whilst the Dark Lord traveled to Mustafar to rescue his grievously injured apprentice.
The aftermath of the duel between Jedi Master Mace Windu and Darth Sidious left young Anakin Skywalker in turmoil. After the death of Windu under the hands of both Skywalker and Sidious, Skywalker agreed with Sidious who told him the dark side's power to cheat death and joined the dark side and became Darth Vader. With fear of losing his wife, Padmé Amidala, Vader had to grow strong within the dark side in order to know the power. Sidious had sent him to the Jedi Temple to kill all the Jedi that resided in there. After the Jedi's defeat in the Temple, Sidious sent Vader to Mustafar to kill the remaining members of the Separatist Council and end the Clone Wars, which plagued the galaxy for four years.
Jedi Master Obi-Wan Kenobi and Yoda, the Jedi Grand Master, managed to enter the Jedi Temple a day after Operation: Knightfall, which was Vader's mission to kill the Jedi inside the Temple. Revealing the fall of his former apprentice, Kenobi witnessed Skywalker killing Jedi from security holograms. Kenobi, on Yoda's orders, left to find Vader who was on Mustafar, a volcanic planet in the Outer Rim Territories. Yoda hoped that should they both succeed that the galaxy would be free of the threat of the Sith. Yoda entered the Chancellery Secretariat undetected, determined to kill the new Emperor, Palpatine, who was revealed to be a Sith Lord, Darth Sidious.
Inside the Chancellor's holding office of the Senate Building, the Jedi Grand Master came face to face with the Dark Lord of the Sith after making short work of his guards. Realizing that a battle between two masters of the Force was imminent, Mas Amedda promptly left the office.
The battle started with the Emperor blasting Yoda with Force lightning, sending him flying across the chamber and slamming into a wall. Yoda quickly recovered, and ignoring Sidious' taunt, retaliated with a powerful Force push that bowled the Sith over his desk. Not wanting to take any risks at his moment of triumph, Palpatine attempted to flee, but Yoda blocked his way and ignited his shoto. Realizing he would have to fight the Jedi Master blade-to-blade, Palpatine ignited his hold-out lightsaber, and the two engaged in an intense lightsaber combat.
Their battle wound through the office, with neither opponent able to take the advantage. However, as the fight moved on to the Chancellor's podium, it started rising through the retractable ceiling into the Grand Convocation Chamber itself. The duel continued, increasing in speed and ferocity, but Sidious became more and more hard-pressed, as he was hampered in his movements by the confines of the pod, while Yoda could easily jump around him. Facing serious danger, Sidious decided to change tactics. Laughing manically, he took the higher ground, jumping to one of the higher Senate pods. In a powerful example of Dun Möch, Palpatine attempted to overpower Yoda with an avalanche of levitating Senate pods while levitating his own, laughing maniacally at his own demonstration of power, and seeming to grow more amused as the battle progressed. Despite the massive amount of Force energy Sidious commanded, Yoda was able to avoid being crushed by the improvised projectiles, using his own powers to dodge from one pod to another, but unable to close to lightsaber range against the Dark Lord again.
It was at this very moment, during the clash between light and dark, Yoda finally saw the truth: He had lost the fight even before it had started. In the last millennium, the Sith had changed, grown, adapted, become new; while the Jedi Order, under Yoda's leadership, spent the same millennium merely training to refight the last war.
Yoda understood that this new Sith Order could not be destroyed by merely a slash of a lightsaber. With this new insight, Yoda understood that he could not fall right there, but instead, he had to share this discovery. Shaking away his doubts, the tiny Jedi focused himself on an oncoming pod and stopped it dead centimeters before him. Sidious' laughter died and was replaced by a frow of annoyance as he realized that his Dun Möch was no longer effective, and worse, that he had stretched his telekinetic powers too far and that Yoda had now taken control of the projectile and was hurling it right back at him. Seeing Sidious jumping down to avoid being crushed, Yoda saw a chance to reengage him at close quarters and leapt at the Sith Lord, igniting his lightsaber. Sidious however recovered quickly, and unleashed a blast of Force lightning at Yoda before he could strike, tearing the lightsaber from Yoda's grasp. Sidious then started to laugh again: with his opponent disarmed, he believed all that remained to do now was to barrage Yoda with Force Lightning and end him just like Mace Windu. His laughter died as he saw that Yoda managed to stop his lighning barehanded, and his expression turned to outright alarm as Yoda started sending the energy back. As both masters were of equal strength, the energy started building up between the two, forming a ball lightning that eventually exploded, catapulting both backwards. While Yoda fell down to the holding office, Palpatine managed to grab and hold on to the edge of the pod they were fighting on. Sensing troopers would soon arrive, and unable to bring the fight back to his opponent fast enough, Yoda was forced to flee, while the Emperor cackled behind him, but was too tired to give pursuit. He crawled through the ventilation shafts and eventually dropped into Senator Bail Prestor Organa's airspeeder.
Shock troopers led by Commander Thire were not able to recover Yoda's body, and Mas Amedda was convinced that the Jedi Grand Master had escaped. Emperor Palpatine had no choice but to assign Thire for the search, as he had to leave for Mustafar immediately—he sensed that his apprentice, Lord Vader, was in mortal danger. On Mustafar, the Dark Lord found his apprentice near to death; Obi-Wan Kenobi having dealt him what seemed mortal wounds. However, Sidious ultimately managed to save his apprentice.
The magnitude of damage in the Senate Rotunda caught the eyes of the Senators. Rumors circulated in the Senate that Jedi Grand Master Yoda had led an attack on Emperor Palpatine himself, and that the ancient Jedi Master had been killed. Through Wookiee Senator Yarua, the rumor found its way to Kashyyyk, including the ears of Chewbacca and Tarfful. Eventually the rumor reached Olee Starstone and her team of fugitive Jedi.
Having failed, Yoda chose self-imposed exile to the swamp planet of Dagobah, where he would wait until the offspring of Anakin Skywalker, the twins, Luke and Leia, would be of age to turn their father back from the Dark Side and return the balance to the Force that their father failed to do. Years later, on Dagobah, Yoda would train Luke in the ways of the Force. Luke would ultimately go on defeat Palpatine and rescue his father from the dark side.
This lightsaber duel in the Senate Rotunda was created for the 2005 film, Star Wars Episode III: Revenge of the Sith. This was the second lightsaber duel to occur in the Senate Building, with the previous one being Exar Kun slaying his former Master, Vodo-Siosk Baas, in the old Senate Hall. During the animatics stage, Steven Spielberg participated in the production of the duel. According to The Making of Star Wars Revenge of the Sith, Senate hovercams were meant to broadcast the duel across the galaxy on the HoloNet. This idea was later dropped.
The movie does not explain the whereabouts of Palpatine's lightsaber when he starts applying Dun Möch. Many fans speculate he discarded it or put it away to start a Force duel. Others believe he was disarmed. Neither explanation has been proved or disproved.
In the novelization, Yoda entered the office from another direction, so no Royal Guards attempted to stop him. Mas Amedda left the office before any exchange was made. Palpatine's Force lightning was deflected by Yoda which blasted the guards into unconsciousness instead of himself being knocked across the room. Yoda then knocked Palpatine to the floor with his physical body instead of a Force Push. At the end of the battle, the lightning energy ball did not explode. Sidious safely leaped to a nearby podium and Yoda followed. Sidious then turned around and blasted Yoda, who was still in the air, back against another podium who fell down to the bottom. Sidious was not knocked over by any blast, he was described as "a very old, very tired man" after the epic battle. In the novelization, Yoda apparently does not lose his lightsaber in the battle as he is described as slicing his way through the ventilation shafts.
In the comic, the first half of the duel is a combination of scenes in the movie and the novelization. Yoda entered the office the way he did in the novel, but was blasted by Palpatine as shown in the movie. The Red Guards and Mas Amedda mysteriously vanished after the battle started, and Yoda knocked Palpatine down with his body as shown in the novel. The duel in the comic ends after Yoda disarms Darth Sidious and gets blasted into the air.
There is a contradiction between two official sources about whether Yoda truly fainted or was merely playing weak when Sidious shot him with lightning and sent him flying across the office; the screenplay described Yoda as "stunned," while the junior novelization stated that Yoda faked it to surprise Darth Sidious. As the screenplay is G-canon, it is the official version.