Mission to Mustafar/Legends

"The Chancellor has given me a very important mission. The Separatists have gathered in the Mustafar system. I'm going there to end this war. Wait for me until I return&hellip; things will be different, I promise."

- Darth Vader to Padmé Amidala

In 19 BBY, Darth Sidious, the Dark Lord of the Sith and Supreme Chancellor of the Galactic Republic, sent his new apprentice, Darth Vader on a mission to kill the remaining members of the Separatist Council on the volcanic planet of Mustafar. The Council, consisting of the surviving top members of the Confederacy of Independent Systems, was a loose end in Sidious' plot to gain control of the Republic and mold it into the galaxy's first empire. Vader willfully carried out the slaughter after he trapped the council in their war room, where he slew each Separatist leader, one by one. The slaughter ended with the death of Nute Gunray, the Viceroy of the Trade Federation, who was one of the most influential members of the Council.

As the bloodshed came to an end, Vader received the order to send a shutdown signal to all battle droids part of the Separatist Droid Army, ending the Clone Wars, that, for the past three years, had spread across the galaxy. This, coupled with the Chancellor's Declaration of a New Order before the Galactic Senate, secured Sidious' position as the Galactic Emperor of the New Order. Before Vader could leave the planet, he was confronted by his wife, Senator Padmé Amidala of Naboo, who inadvertently smuggled Vader's old master, Obi-Wan Kenobi, to Mustafar. Confusion ensued when the Jedi Master revealed himself, and Vader, believing that Amidala had brought Kenobi to kill him, flew into a rage, and Force choked Amidala; she survived her husband's wrath, but was knocked unconscious.

Kenobi attempted to turn Vader away from the darkness, but the young Sith Lord was too furious to be reasoned with, and he attacked his former teacher, beginning an epic duel between the two former brothers-in-arms, in which Kenobi grievously wounded Vader, who, after his immolation, was left on a river of lava to die. Sidious, however, arrived on the planet, and took his apprentice's ruined body to Coruscant, where Darth Vader was rebuilt into the figure who was feared, as the Empire's most deadly servant, until mere minutes before his death.

Prelude
"The plan has gone as you had promised, my Lord.''" "''You have done well, Viceroy. When my new apprentice, Darth Vader, arrives, he will take care of you."

- Nute Gunray and Darth Sidious

During the Confederacy of Independent Systems' invasion of the galactic capital, Coruscant, Count Dooku, the Head of State of the Separatist Council and the Confederacy, was executed by the Jedi Knight Anakin Skywalker at the urging of Palpatine, in actuality Dooku's master, Darth Sidious. Following this loss, General Grievous, the Supreme Commander of the Separatist Droid Army, became the political leader of the Separatists as well and took control of the Council, which at the time was based on the sinkhole planet Utapau.

Grievous's first action, under Sidious's guidance was to transfer the Council from Utapau to Mustafar: Sidious knew of the impending offensive on Utapau led by General Obi-Wan Kenobi. The Council settled itself into the Klegger Corp Mining Facility. Around this time, an assassination attempt on Sidious led by the renowned Jedi Master Mace Windu resulted in Anakin Skywalker becoming Sidious's new Sith apprentice, given the moniker Darth Vader. Vader, believing wholeheartedly in Sidious's abilities to save his wife, Padmé Amidala, from death, led the 501st Legion of clone troopers to the Jedi Temple to massacre the Jedi Order.

Following the destruction of the Jedi Order, Sidious had no further use for the Separatists. He ordered his apprentice to go to Mustafar and kill the surviving members of the Separatist Council. Sidious told Nute Gunray, the Viceroy of the Trade Federation, that his apprentice would reward them for their loyalty during the Clone Wars by 'taking care' of them (a clear euphemism for their impending slaughter). In addition to this, Viceroy Nute Gunray was named Head of State of the Confederacy of Independent Systems, a title which he would hold for a limited time.

The assassinations
"Welcome, Lord Vader. We've been expecting you."

- Nute Gunray

When Darth Vader arrived at the control bunker on Mustafar, Nute Gunray, San Hill, and the other members of the council welcomed him. At the time, the Separatist leaders were demoralized by their recent defeats in the Outer Rim Sieges, the loss of Count Dooku, General Grievous and their sudden withdrawal from Utapau shortly before the battle. Many of them wanted to sue for peace with the Galactic Empire, formerly the Galactic Republic.

However, upon his arrival, Vader immediately closed the doors of the bunker, trapping the Separatist leaders, their aides, and several B1 battle droids within. Engaging in a rampant killing spree, Vader destroyed the battle droids and killed the members of the Neimoidian Gunnery Battalion before looking to his targets. Vader first slaughtered Denaria Kee, Aito Laff, Po Nudo, and Passel Argente. The remaining Separatists fled. Vader went after them and killed Nank Tun, Cat Miin and Shu Mai. Vader then strode after and killed Tikkes, San Hill, Nudo's Aqualish aide, Poggle the Lesser and Aruteous Gunnay next while Nute Gunray watched in horror. Rune Haako and Wat Tambor fled into the conference room to avoid Vader, but Vader slaughtered both Haako and Tambor. Vader finally cornered Nute Gunray, whom he despised most of all for his attempts to kill Padmé Amidala, Vader's beloved. Gunray pleaded for his life but to no avail; Vader executed him. As he surveyed the carnage, his eyes turned a red-rimmed yellow, a trait common among those immersed in the dark side. Unbeknownst to the Separatists, Sidious was secretly watching the carnage inflicted by his Sith Apprentice as he left his comm link on, just before the Declaration of the New Order.

Aftermath
"The Separatists have been taken care of, my master.''" "''It is finished, then. You have restored peace and justice to the galaxy."

- Darth Vader and Darth Sidious

With the death of the Separatist Council, Vader received the order to end the Clone Wars by sending a shutdown signal to the entire Separatist Droid Army and Confederate Navy. Without their droid army and navy, to protect them, the remaining Separatist planets were forced to surrender to the Empire and live under Imperial rule. This action effectively ended all combat operations between the Galactic Empire and the Confederacy of Independent Systems across the galaxy.

Before Vader left the planet, his wife Padmé Amidala arrived to question him about his involvement with the massacre at the Jedi Temple on Coruscant. She hadn't realized that Obi-Wan Kenobi, Vader's former master, had smuggled himself on board her ship. When Kenobi revealed himself to Vader, it looked as if Amidala had brought him to Mustafar to confront him. Believing himself betrayed, Vader choked his wife into unconsciousness. Kenobi also tried to reason with his former Padawan, but without success. Kenobi was forced to fight Vader. Vader was severely injured in the ensuing duel, but was rescued by Palpatine and some clone troopers. However, his condition was so critical that he was forced to spend the rest of his life in a life support suit.

After the massacre of their leaders, the Trade Federation and the Techno Union were forced to turn over their assets to the Empire, the former of which attempted a last stand against the Empire, while the Corporate Alliance and the Commerce Guild were quietly dissolved. The InterGalactic Banking Clan, however, survived the catastrophe, though it was much less successful than before.

Behind the scenes
This mission was first depicted in Star Wars: Episode III Revenge of the Sith, released in 2005.

In the Revenge of the Sith video game, Vader is depicted fighting his way through the mining facility after killing two aides at the landing platform and battling battle droids and Neimoidian guards. Upon reaching the war room, Vader kills Poggle the Lesser with the room's blast door and kills Wat Tambor, two unidentified Neimoidians, and Rune Haako, who pleads for his life before dying. As Nute Gunray attempts to escape in his shuttle, Vader brings it down into the lava below.

The Revenge of the Sith novelization depicts Vader as killing each of the Council members in a particularly brutal way, and responding to the Separatists' pleas for mercy with amusing one liners and witty wordplay. In particular, he responded to Nute Gunray's pleas of Sidious's promise to leave them "in peace" with the remark, "His transmission was garbled. He promised to leave you in pieces." Also notable is that this version marks San Hill as the first casualty, followed by Poggle, then Shu Mai, then Rune Haako, then Wat Tambor, then Nute Gunray.

Appearances

 * Wat Tambor and the Quest for the Sacred Eye of the Albino Cyclops
 * Star Wars: Episode III Revenge of the Sith
 * Star Wars Episode III: Revenge of the Sith comic
 * Star Wars Episode III: Revenge of the Sith novel
 * Star Wars Episode III: Revenge of the Sith video game
 * Star Wars Episode III: Revenge of the Sith junior novel
 * Dark Nest II: The Unseen Queen
 * Dark Nest III: The Swarm War