Attack on Castilon

In 34 ABY, early in the First Order–Resistance war, a battle took place on Castilon, which ended with the Colossus escaping the planet and the First Order forces that had occupied it. The platform, an old Imperial super tanker fuel depot, had not flown in at least twenty years prior to the battle, but after Resistance member Kazuda Xiono and Neeku Vozo discovered the station's hyperdrive, Xiono had Vozo get the drive working again so they could escape. Captain Imanuel Doza, the Colossus' owner, cautiously approved the plan when he was informed of it. Xiono, CB-23 and Torra Doza, at Vozo's suggestion, lured the station's garrison of stormtroopers into areas of the station that were then flooded, flushing the troopers into the ocean in order to clear the Colossus of its occupiers. The chaos led Agent Tierny of the First Order Security Bureau and Commander Pyre to decide to abandon the Colossus and call in reinforcements to destroy it in order to cut their losses, taking Tamara Ryvora, a former member of Team Fireball who had been manipulated by Tierny into believing Jarek Yeager and Xiono, her friends, were evil and had been using her all along, with them. Xiono and Yeager attempted to persuade Ryvora to stay, but were unsuccessful. When Pyre ordered them to surrender, Xiono instead had Vozo activate the Colossus' engines, raising the station. Tierny and Pyre then escaped on their shuttle with Ryvora.

As the station rose into the air, the Ace Squadron, along with Yeager and Xiono, headed to their ships. The timely arrival of Hype Fazon and Z'Vk'Thkrkza in the AAL-1971/9.1 Troop Transport they had stolen to earlier escape the station, having picked up the distress signal Xiono had earlier sent, allowed the fighters to launch against the TIE fighters led by Major Elrik Vonreg. During the battle, the Colossus' defenders were joined by the Warbird pirate gang, eager for revenge for the First Order's earlier betrayal of them, as persuaded by Synara San, who had befriended Xiono while spying on the station. The Colossus was high in Castilon's atmosphere when a Resurgent-class Star Destroyer arrived to destroy the station, leading Xiono to order everyone to the safety of the Colossus so they could jump into hyperspace. However, they weren't quite high enough yet, and Yeager was being pursued by Vonreg. Xiono ambushed the red-armoured pilot by flying between the top and bottom of the Colossus, shooting him down from behind, before he and Yeager landed in a hangar. The Colossus reached the edge of Castilon's atmosphere and jumped into hyperspace, with the intended destination being the Resistance base on D'Qar, per coordinates given by Xiono to Vozo. However, Vozo, short on time, hadn't inputted the entire coordinates, and Yeager and Xiono were displeased to learn that the station's destination was now uncertain.

Prelude
In the months before the beginning of the First Order–Resistance war, the First Order, preparing for the conflict, became interested in using the Colossus platform on Castilon as a base and staging area. The Resistance, becoming aware of the First Order's interest, sent newly-recruited spy Kazuda Xiono to the Colossus on his own mission to determine if anyone on the platform was working with the First Order. As part of his cover, he worked as a mechanic at Jarek Yeager's repair shop, alongside Yeager's other employees, Neeku Vozo and Tamara Ryvora. Yeager, an old friend of Commander Poe Dameron, was reluctant to hire on Xiono, and warned him he didn't want anything to do with his mission. Xiono was initially accompanied by Dameron's astromech droid, BB-8.

In order to take over the Colossus, the First Order, on the suggestion of Commander Pyre, hired the Warbird gang of pirates, led by Kragan Gorr, to attack the station regularly, hoping to pressure the Colossus' owner, Captain Imanuel Doza, into inviting First Order forces onboard as security. Doza was highly reluctant to do so, as he distrusted the First Order. After arriving on the Colossus, Xiono experienced several of the pirates' attacks. After the Warbirds were able to get a spy, Synara San, onto the platform due to the unwitting actions of Xiono and Dameron, who rescued San from the aftermath of a botched raid without knowing who she was, the pirates carried out a particularly devastating attack, which caused enough damage that Doza was forced to reconsider the First Order's offer. When Pyre came to the Colossus to give Doza a copy of the proposed offer, Xiono snuck into Doza Tower and stole a copy via his friendship with Doza's daughter Torra. However, Torra was aware that her father suspected Xiono of being a spy, thanks to having drawn his attention earlier.

Eventually Pyre and Captain Phasma, frustrated that Doza was taking an unacceptably long time to give a decision about their offer, had the Warbirds kidnap Torra for triple their usual pay. San, ordered to help the pirates who would be doing the kidnapping, was taken aback, having befriended Torra and Xiono during her time on the Colossus, and her decision to get Xiono involved trying to stop the kidnapping led to him discovering that she was a pirate. When Major Elrik Vonreg arrived to pay the Warbirds, he instead betrayed the group and "rescued" Torra, which was witnessed by Xiono and a few of the other pilots of the Ace Squadron, who had pursued the pirate abductors. The ruse gave the First Order leverage with Doza to station stormtroopers permanently on the Colossus, beginning an occupation. The new garrison's first order of business was locating and arresting the pirate spy. Despite his misgivings, Xiono helped San escape the Colossus, with the assistance of Vozo. The incident, however, gave Pyre an excuse to increase the crackdown, on the grounds that a station resident had clearly assisted the spy in her escape. Xiono, while impersonating a stormtrooper, learned that when the full garrison arrived, the FIrst Order intended to arrest any Colossus residents who refused to support them,

The First Order's occupation also caused friction between Xiono and his co-worker Ryvora. As Ryvora's grandfather had once worked in an Imperial factory, she did not view the First Order as a problem, and was sympathetic to them. When Xiono and Yeager attempted to warn Ryvora about the true nature of the First Order, she brushed off their warnings. As part of the occupation, the First Order instituted a communications blackout that prevented Xiono from contacting the Resistance. Eventually, he attempted to build a transmitter to get past the jamming, but it didn't work. However, that same day, Commander Dameron snuck back onto the Platform to retrieve BB-8, as he and the droid had been assigned a mission to Jakku. Xiono, Dameron and BB-8 slipped off the Colossus in the Fireball using a Widowmaker maneuver to rendezvous with Dameron's X-wing and CB-23, the droid who would be replacing BB-8. The two pilots investigated the Dassal system and had a skirmish with Major Vonreg before exchanging droids and parting ways.

Shortly after Xiono's return, Commander Pyre successfully pressured Captain Doza into ending the races on the station by claiming that the racers could be connected to the pirates. In actuality, the First Order wished to remove the Ace Squadron, who served as the Colossus' defence force, as a threat. This angered Hype Fazon, the leader of the Aces, and led to his arrest when he ran into some stormtroopers affixing a gravity lock to his ship. After Fazon's arrest, Z'Vk'Thkrkza, proprietor of Aunt Z's Tavern, was arrested for refusing to have First Order propaganda in her establishment. This led Xiono, Torra and CB-23 to sneak out that night and rescue Fazon, Aunt Z and two others, Grevel and Nod, from First Order custody. Fazon and Aunt Z escaped the planet on the AAL-1971/9.1 Troop Transport which would have taken them to prison, intending to head to Takodana, where Aunt Z had a friend. However, when Xiono and CB-23 returned to the repair shop afterwards, they found that Pyre had placed the rest of Team Fireball under arrest. Pyre told Yeager that the crew was under arrest for consipiring against the First Order, as the Fireball had been identified as a ship flown by Resistance agents trespassing in Sector 51-3, which was restricted space. Yeager, Xiono, Vozo and CB-23 were able to escape with the help of R1-J5, aka "Bucket", who had been in the back of the shop when the stormtroopers arrived, escaping notice. However, during the escape, Bucket was shot and fell into the ocean, and Ryvora, believing the situation to merely be a misunderstanding, did not run and was captured.

Fleeing through the Colossus' maintenance ducts, Xiono admitted to a confused Vozo that he was a spy, which the literal-minded Nikto initially mistook as a joke. Xiono, Vozo, Yeager and CB-23 were nearly caught by stormtroopers before being rescued by the Chelidae engineering staff and siblings Kel and Eila, a pair of young fugitives from the First Order Xiono had previously assisted. In engineering, Xiono came up with a plan to contact the Resistance by sinking the Colossus almost entirely underwater to make it easier to access the transmitter broadcasting the First Order's jamming signal. Xiono, Yeager and CB-23, with the assistance of Captain Doza, were able to smoothly sink the platform, make it to the transmitter and send and receive a message, but Yeager was arrested while ensuring Xiono and CB-23's escape. Furthermore, the message from General Leia Organa was not good news: she regretfully informed Xiono that the Resistance had no forces to spare to help at that time. Xiono therefore resolved that he and his allies would take back the Colossus themselves. Unbeknownst to Xiono, the signal was picked up by more than just the intended recipients: the Warbird gang and Fazon and Aunt Z also intercepted it.

Meanwhile, Ryvora was questioned by First Order Security Bureau Agent Tierny. The agent, a skilled manipulator, used Ryvora's sympathy for the First Order and her feelings of confusion and betrayal when she was informed of Xiono and Yeager's Resistance connections to convince her that they and the Resistance were evil and had been using her all along, and that she would be much better off siding with the First Order. When Yeager gave a false confession claiming he had been the spy all along to try and divert blame from Xiono, Tierny used that as well. This all had the effect that the next time Yeager encountered Ryvora, he was unable to break through to her that she was being manipulated. The news of Yeager's arrest led Doza to confront Pyre, and he was arrested after a scuffle in his office. Torra witnessed it from a hiding place, and this led her to send her pet Buggles in search of Xiono so they could work on a rescue plan. Xiono, meanwhile, had come up with a plan that involved rescuing Yeager and Ryvora, stealing the shuttle and heading to his homeworld of Hosnian Prime for reinforcements. As part of this plan, Xiono and Vozo took over a control room deep in the station from the stormtroopers stationed there.

When Xiono and CB-23 headed out for the tower, they had an encounter with SCUBA troopers before they managed to get back inside the station. Meanwhile, Vozo, Eila and Kel discovered that the room contained a hyperdrive, which came as a surprise to the Nikto mechanic, and he contacted Xiono about the discovery. Shortly after leaving the Office of Acquisitions empty-handed, Xiono and CB-23 were located by Buggles, who led them to Torra's hiding place in a maintenance duct. Torra informed Xiono about her father's arrest, and after a near-miss at being discovered, which led to CB-23 destroying an enemy droid, they headed off to the tower. Shortly after arriving in the tower, Torra sent Buggles back to her room. Xiono noticed that the hallways were much quieter than would be expected. They overheard two stormtroopers discussing the recently-completed Starkiller Base, and followed them to see several troopers watching a broadcast of General Armitage Hux ordering the superweapon to fire on the Hosnian system. Xiono was horrified when he realized that his homeworld had been destroyed, However, Torra persuaded him that they had to move on before they were discovererd, and Xiono vowed that the First Order had to be defeated.

Clearing the station
Xiono and Torra reached the cell where Doza and Yeager were being held, and CB-23 opened it. The captives were happy to see their rescuers, but Yeager quickly noticed something was wrong with Xiono, who told him about the Cataclysm. Yeager and Doza were horrified and sympathetic. Xiono and Torra told them about the plan to have Vozo fire up the Colossus' engines and launch it into space. Doza had some misgivings about the plan, as he noted that the station had not been into space in twenty years. However, there were few other options. Vozo, talking with Kel about the fact that the Colossus had to purge the water it had taken on before it could launch, had an idea that the stormtroopers occupying the station could also be disposed of this way, and contacted Xiono about it. Xiono was less than enthusiastic about having to put himself, CB-23 and Torra in physical danger for the plan to succeed, but okayed it. As Xiono, Torra and CB-23 headed to the submerged levels to work on getting rid of the stormtroopers, Yeager and Doza went to sneak into the captain's office.

Xiono, accompanied by CB-23, and Torra, alone, positioned themselves carefully in the corridors, before Xiono contacted Vozo to give him instructions for the operation. Vozo misinterpreted things and started the partial flooding early, but it worked as planned, with the stormtroopers trapped in flooded sections and then flushed into the ocean. Torra carried out her part of the plan on her first squad of troopers. As Xiono and Torra worked their way through the troopers, the ones in the ocean became food for some of Castilon's wildlife. In Doza's office, Commander Pyre, after receiving reports of the losses, was told by Agent Tierny that backup was in order, as she intended to leave the station with Ryvora soon. Pyre eventually agreed, and hinted that it would be better to cut their losses and destroy the Colossus outright. Yeager and Doza, hidning in the office, heard the conversation, and after Pyre, Tierny and their troops left escorting Ryvora, Yeager contacted Xiono, dealing with the last of the stormtroopers, to tell him about the First Order's plans to take Ryvora away. They agreed that they had to try and stop it. Meanwhile, down in the hyperdrive room, Vozo was surprised when informed that they were receiving a message from Aunt Z.

Taking to the sky
Ryvora was escorted outside by Tierny and Pyre to the side of the top of Doza Tower, where a shuttle descended to pick them up. Doza had gone to free the arrested Aces from the holding cells. Yeager emerged from a slightly lower level, and implored Ryvora to stay, trying to get her to understand that the First Order was lying to her. From the top of Doza Tower, Xiono, accompanied by Torra and CB-23, also tried, Xiono admitting that he did work for the Resistance. Tierny stopped Pyre from shooting at them. Ryvora, upset with them for lying to her and supposedly manipulating her, refused to listen, and eventually stormtroopers arrived and cornered Yeager, Xiono, Torra and CB-23. Pyre demanded their surrender. Xiono, unconcerned, instead ordered Vozo via comlink to activate the Colossus' engines. Tierny was surprised at the Resistance members' course of action, while Ryvora was surprised that the Colossus was capable of space travel. The sudden shaking threw the stormtroopers off-balance, sending some of those confronting Yeager falling to their doom, while CB-23 used her cables and oil to send the troopers cornering her, Xiono and Torra over the edge of the catwalk. She also caught Torra when the girl fell over the edge. Pyre and Tierny jumped onto their shuttle, and Tierny offered Ryvora her hand. To Yeager and Xiono's audible dismay, Ryvora chose to take the agent's hand, and the shuttle swiftly departed with her on board. Torra, lowered to the ground, told Yeager how sorry she was, but he responded that Ryvora had made her choice. Joined by Xiono and CB-23, Yeager led them inside, suggesting that they get to their ships to defend the platform. Down in the holding cells, Doza released Freya Fenris, Griff Halloran and Bo Keevil and ordered them to prepare to defend the Colossus.

Upon reaching the hangar where the Fireball and his own ship had been moved, Yeager ordered CB-23 to remove the gravity locks, and Bucket to head to the hangar with the Aces' ships and do the same. When CB-23 opened the hangar door, however, Yeager, Xiono and Torra were greeted by two TIE/fo space superiority fighters, which prevented them from launching. Fortuitously, however, at this time Fazon and Aunt Z arrived in their transport and were able to shoot down the fighters. Fazon told Xiono that he and Aunt Z had picked up his distress signal. Upon attack from more fighters, Fazon and Aunt Z returned to flying their ship, as Xiono, Yeager and the other Aces launched their fighters. Initially, their opponents were only regular TIE fighters, as the fight wove around the ascending Colossus. When Vonreg joined the fight, the first thing he did was damage Halloran's Black Ace, but Xiono helped him get rid of his pursuers. The arrival of the Warbirds' ship Galleon helped ease the burden some, as San had persuaded them to come and help, in part to get revenge on the First Order for their betrayal. Xiono was glad to see San again.

The arrival of a Resurgent-class Star Destroyer, which opened fire on the station, alarmed the Colossus' defenders and their allies, prompting Xiono to order everyone back to the safety of the station, and send Vozo the coordinates for the Resistance's base on D'Qar. However, Captain Doza pointed out that the Colossus was not yet far enough above Castilon's surface to safely jump into hyperspace. Furthermore, Yeager requested help as he was being pursued by Major Vonreg. Xiono went out to help Yeager and, noticing the flight path the two were taking, hit upon an idea. He flew the Fireball into the narrow space between the upper structure of the Colossus and the lower part with the engines, too narrow for a TIE to enter, and came out behind Vonreg, ambushing him and shooting him down. Yeager complimented him on the assist before the two entered the hangar. The Colossus, having reached Castilon's upper atmosphere, subsequently jumped into hyperspace.

Aftermath
After the Colossus was safely in hyperspace, the pilots and various others gathered in the hangar. Xiono and Yeager, while talking, expressed their regret that they hadn't been able to stop Ryvora from going to the First Order. They were then accosted by an excited Vozo, who cheerfully informed them that he'd run out of time to input the entirety of the coordinates into the hyperdrive, so the Colossus was likely to wind up at a destination somewhere between Castilon and D'Qar. Yeager and Xiono were concerned by the news, but concluded that the only thing they could do was wait and see where they emerged.