The Grand Festival of Empress Vaylin was a lavish party thrown by Vaylin, Empress of the Eternal Empire of Zakuul, to celebrate her glory after the recent victories over the Alliance that opposed her. Meanwhile, the Alliance launched Operation Dragon's Maw, using the party to get close enough to Vaylin for a strike. Magistrate of Revelry Indo Zal who organized the party secretly hated Vaylin for years and contacted the Alliance with a plan on how to bring her down, offering to provide disguises and security clearances for Theron Shan and the Alliance Commander in exchange for them saving captured Zakuulan rebels from public execution during the party. The Commander held a key to Vaylin's mental conditioning, but required a diversion to get close enough to trigger it, which the rebels were meant to provide. The Commander and Theron Shan traveled to the Palace of the Eternal Dragon disguised as two Knights of Zakuul, while Lana Beniko provided remote support from a nearby shuttle. After meeting with Indo Zal, Theron and the Commander installed Ion charges throughout the Palace to disable the rebels' shock collars. when Vaylin began her speech, the Commander triggered the ion charges which freed the rebels and activated Vaylin's conditioning, making her powerless to retaliate. However, their confrontation was interrupted by arrival of Vaylin's brother and former Emperor Arcann, who arrived with a group of loyalists and attacked the Palace. After saving the rebels from execution by fighting beasts, Theron and the Commander pursued Vaylin and interrupted the duel between siblings, inadvertently allowing Vaylin to escape. Arcann then offered to join the Alliance to atone for his past crimes, and the Commander agreed to take him in, but Vaylin ordered the Eternal Fleet to bombard the entire Palace to rubble, with her supporters still inside. Lana picked the Commander, Theron and Arcann in a shuttle just before the entire Palace collapsed, killing multiple civilians and tarnishing Vaylin's public image among the people of Zakuul.
After regaining full control of the GEMINI captains that commanded the Eternal Fleet, Eternal Empress Vaylin send it to attack Alliance outposts and patrols. To celebrate her victory, Vaylin ordered her Magistrate of Revelry Indo Zal to organize a Grand Festival at the Palace of the Eternal Dragon in her honor. During the party, Vaylin planned to execute a host of captured Zakuulan rebels by feeding them to wild beasts. However, Indo long desired to have revenge on Vaylin for the murder of his sister Kalya and contacted the Alliance base on Odessen, offering to provide them with a way to strike at Vaylin at the party. After Theron Shan and T7-O1 vouched for him, Indo volunteered to prepare disguises and security clearances that would allow the Alliance Commander to get inside the Palace and trigger mental condition imposed upon Vaylin by her father. The plan required a distraction, and Indo offered to free and start a revolt among the captured rebels, causing enough chaos for the Commander to get close to Vaylin. The mission was code-named "Operation Dragon's Maw" and Theron Shan volunteered to accompany the Commander, while Lana Beniko and T7-O1 provided remote support by slicing into the security grid from a shuttle that served as their getaway vehicle.
The party was impressive, with Zakuulan socialite gathering in the Palace of Eternal Dragon and toasting in Vaylin's name. However, leaving during the party was strictly forbidden and speaking during the royal address was punishable by death. To add to their humiliation, captured prisoners were forced to serve drinks to the guests while awaiting their execution. The fighting beasts themselves were either restrained in place on the main floor, or kept in the beast pens in the lower level, where beast master Oleg oversaw the menagerie. Music by Raz and the Ubo-Kings, a band that exploded in popularity on Zakuul, was played to entertain the guests, although the band themselves could not make it to Zakuul. Several dishes were served during the event, with six hundred bottles of Zakuulan wine ordered alone, although chef Areta Foss found the glazed kell cooked by her droid assistant not up to standards, ordering to throw out all thirteen prepared batches. Complimentary holograms of Empress Vaylin were provided to the guests at the reception area, while the HoloNet drones broadcast the party for all the galaxy to see. Security was provided by Knights of Zakuul and Vaylin's personal Horizon Guard stationed throughout the Palace.
Arriving on Zakuul wearing the the guises of two Knights of Zakuul, Theron and the Commander got inside the Palace and met with Indo Zal. He provided them with Ion charges to be attached to security relays throughout the Palace, so that they could be detonated at once and disable the rebels' shock collars. Leaving the task to the Alliance, Indo returned to Vaylin's side, however he was caught spying on her during a holocall with Jarak, which blew his cover and earned him a collar of his own. Theron and the Commander worked their way around Palace security dressed as Zakuul Knights, using clever deception to gain access to unauthorized areas. Among other things, the Commander stole a Knight-Captain's shield, which allowed them to threaten the other Knights with their rank, stole a foreman access card from one of the dock workers, lifted the lockdown from the security room to access the data in the server room and fed medicine to a sick exoboar Bergola in the beast pens, earning the creature's gratitude.
After Theron and the Commander planted all six charges, Lana informed them that Vaylin was beginning her speech ahead of of schedule. Dropping their disguises, Theron and the Commander strolled into the main hall, where Vaylin was making the public address to the holocameras. Having uncovered Indo's deception, she made a speech about Zakuul's glory and her enemies' torment, when the Commander publicly mocked her in front of the cameras, causing Vaylin to drop Indo and the other prisoners inside the beast den. Vaylin used the Force to levitate heavy mental ornaments, intending to smash the intruders with them, but the Commander spoke the code phrase "Kneel before the Dragon of Zakuul" that triggered her mental conditioning, causing Vaylin to lose control of her powers in front of everyone. The Commander then detonated the ion charges, causing cameras to fail and lights to flicker throughout the Palace as the ion blast disabled all electronics. The remaining rebels began attacking skytroopers and arming themselves with their weapons, while a couple of giant exoboars held on the main floor were suddenly no longer restrained and began causing havoc among civilians and the Knights of Zakuul.
Vaylin ignited her lightsaber and prepared to engage the intruders in combat, when the Palace was hit by a couple of missiles. Unbeknownst to anyone, Vaylin's brother and former Emperor Arcann had also picked the party as the opportunity to confront his sister and arrived with a shuttle full of his loyalists, who began seeking Vaylin throughout the Palace. Seeing her brother on the holocameras, Vaylin retreated from the main hall, all exits from which were then sealed. The only way for Theron and the Commander was to follow the rebels down into the beast den, where they saved Indo and the others from a Rancor named Junior, with an unexpected assistance from Bergola and her pack. The Commander then ordered Indo to retreat with the Rebels to safety, after which they and Theron went to pursue Vaylin, who went to a remote balcony, smashing all holocams in her way. Informed by Lana about Vaylin's whereabouts, Theron and the Commander made their way out of the pit and into the reception area, where a fight between Arcann's loyalists and Vaylin's Knights had broken out, with beastmaster Oleg bringing his two vorn tigers Cho'Kri and Cho'Ale into mix.
Arcann approached Vaylin at the balcony and tried to talk his sister down peacefully, but Vaylin became convinced that her brother was complicit in her conditioning and attacked him in a fit of rage. The two engaged in a lightsaber duel, which was interrupted by the arrival of the Commander and Theron Shan. Seeing a chance to leave Arcann alone with their father's vessel, Vaylin threw a speeder bike at him, which she then used to leave the scene. To the Commander's surprise, Arcann was indeed healed on Voss and addressed them peacefully, acknowledging his past crimes without signs of hostility. After Theron Shan doubted his trustworthiness, Arcann joined him and the Commander in the fight against the Horizon Guard who arrived to kill them. After the Guards were dealt with, Arcann wondered whether the Commander was controlled by his father like a puppet or merely housed his essence.
Valkorion's spirit then revealed himself to Arcann and called him weak, to which Arcann replied that he was no longer his father's son and that the Commander was more deserving of the Eternal Throne than he was. Arcann then offered to join the Alliance to atone for the blood shed under his reign, and the Commander agreed to take him in, using the party holocamers to broadcast Arcann's new loyalty to the galaxy. Witnessing the broadcast from an Eternal Fleet warship she retreated to, Vaylin became enraged at her brother's betrayal and ordered the Eternal Fleet to bombard the entire Palace into rubble, regardless of her supporters still inside. Eternal Fleet ships began laying fire on the Palace, and Arcann, Theron and the Commander rushed to the landing pad where Lana and T7-O1 were waiting for them in the shuttle. Some others managed to escape the Palace in time, but just after Lana's shuttle took off with the Alliance and their new friend safely onboard, the Palace collapsed from the sustained fire, crushing everyone who still remained inside.
What was intended to be a celebration of Vaylin's glory turned to disastrous consequences for the Empress. Her weakness to a mental conditioning became exposed to everyone, and the act of turning on her loyal supporters resulted in her being hated by half of Zakuul's population. Determined to rid of her mental bonds at any cost, Vaylin took her flagship to Nathema, where Jarak promised to have a breakthrough to help Vaylin break her chains. The Alliance meanwhile did not achieve their original goal of taking down Vaylin, but found a new ally in Arcann and secured the support of Zakuulan rebels, who were largely led away from the Palace by Indo. Arcann was brought to the Alliance base on Odessen, where he was initially treated as enemy by the Alliance personnel, but the Commander insisted that having the former Emperor on their side was good for both the morale and for putting additional pressure on Vaylin.
During Chapter VI: The Dragon's Maw player has to perform a certain set of actions to unlock access to the security relays, two of which are optional. One is to lift the lockdown from the server room and obtain the security data from it, which allows Lana Beniko to unlock a shortcut after the fight with the Rancor, allowing the player to skip several fights along their way. The other is to use glazed kell to feed medicine to Bergola, which secures her loyalty and results in her and her pack of Brick, Lil' Jwizzix and Rompy joining the player's side as combat support pets for the second half of the Chapter. If this is not done, all four exoboars will be hostile instead, requiring the player to kill them before engaging the Rancor. After Junior is killed, player can either urge Indo Zal to lead the rebels to safety for Light Side points, or order them to attack the Knights of Zakuul for Dark Side points, the latter of which results in rebels taking heavy casualties and losing their faith in the Alliance.
If during Chapter I: Wrath and Ruin player made a Dark Side choice to kill Senya Tirall, Arcann will not be healed and will arrive seeking vengeance instead of atonement. He will attack the player only be struck down, and Valkorion's spirit will appear to talk to his son one last time before Arcann dies, his life essence secretly absorbed by Valkorion. Afterwards, players can declare themselves Zakuul's protector for Light Side point or gloat at Arcann's downfall for Dark Side points. In the version of events where Arcann survives, players can welcome him into Alliance as an ally for Light Side points or made him openly kneel and swear loyalty for Dark Side points.