Operation: Cinder was the designation given to an orbital bombardment strategy conceived by the Galactic Emperor Darth Sidious. His objective was to penalize the Galactic Empire due to their inability to safeguard him from his own death. Following the Emperor's passing during the Galactic Civil War at the Battle of Endor in 4 ABY, sentinel messenger droids disseminated his posthumous directives to devoted Imperial officers. The targets were numerous planets throughout the galaxy, regardless of their allegiance to the Empire or their participation in open revolt. These targets included Burnin Konn, Candovant, Abednedo, Commenor, and Nacronis, alongside Vardos, a planet renowned for its loyalty to the Empire, and Naboo, the Emperor's homeworld. While Naboo was spared during the Battle of Theed, Vardos suffered immense damage from satellites that devastated its ecosystem. Operation: Cinder served as the initial phase of the Emperor's Contingency. The Empire was intended to be rebuilt within the Unknown Regions, while Sidious secretly underwent revival on Exegol.
Grand Admiral Rae Sloane disrupted the plan by assassinating Fleet Admiral Gallius Rax, the Emperor's protégé, during the Battle of Jakku in 5 ABY. The extensive devastation resulting from Operation: Cinder also led to Iden Versio and Del Meeko, Imperial Special Forces commandos belonging to Inferno Squad, defecting to the New Republic Defense Force. Despite these challenges, the Contingency successfully guaranteed the Empire's resurgence as the First Order, a military junta resolute in reclaiming the Imperial legacy through ending the New Republic Era.
Sheev Palpatine, also known as the Emperor and the secret Dark Lord of the Sith who ruled the Galactic Empire, held the conviction that if his death were to occur unexpectedly, the Empire would be unworthy of survival beyond his existence. He drew a comparison to the strategic game of Shah-tezh, wherein each game piece was tasked with safeguarding an Imperator. Should the Imperator fall, the remaining pieces would be deemed failures, rendering the continuation of the game undeserved. Consequently, he entrusted Gallius Rax, who had known Palpatine since Rax's childhood and later ascended to the rank of Fleet Admiral within the Imperial Navy, with executing a Contingency strategy that mandated the obliteration of both the Empire and its adversaries. The Contingency further stipulated the Empire's rebirth by enabling a select group of Imperial survivors to reconvene in the Unknown Regions for the purpose of rebuilding the Empire. It was also hoped Operation: Cinder would sow fear and remind the galaxy it was the Empire that controlled all, convincing the galaxy against joining a rebel-led government.

Operation: Cinder's targets encompassed both planets loyal to the Empire and those that defied its authority. While another aim of the operation was to destroy sensitive information and other possible liabilities before they could fall into enemy hands, important planets, planets with great resource wealth, and planets that had long since faded from influence were all targeted alike. Given that, in practice, only the loyal would follow Palpatine's wishes during Operation: Cinder while subsequent tactics in the Contingency would cut away whomever was too weak for Rax, the Contingency would ensure that only the most ruthless of the Empire remained to reforge the regime in the Unknown Regions. Although Palpatine had, in secret, designs to ensure his return to life via his Sith Eternal followers on the hidden world of Exegol, Operation: Cinder represented the whims of a man who sought to control the galaxy, even in death. Still, his return to life and subsequent actions would ensure the Imperial regime that arose after the Contingency remained under his control.
Sometime after the Rebel Alliance established its base on Yavin 4 and before their rescue mission to Wobani, the Rebel Alliance Intelligence Service intercepted an Imperial transmission pertaining to Operation: Cinder. According to Capin Harinar's report to Airen Cracken, the project was identified as revolving around a form of climate disruption array. Harinar speculated that if power levels akin to Project Celestial Power were applied, the weapon could trigger planetary heatwaves and boil oceans, essentially functioning as a planet killer.
In 4 ABY, Darth Vader was believed to have killed Emperor Palpatine during the Battle of Endor, resulting in the presumed extinction of the Sith. The Contingency was initiated shortly thereafter. As part of the plan, several worlds were designated for destruction through an orbital bombardment campaign known as Operation: Cinder. Messenger droids were dispatched to chosen Imperial officers to convey the Emperor's final orders: to commence Operation: Cinder immediately.
Following the Battle of Endor, Iden Versio, Commander of the Imperial Special Forces commando unit Inferno Squad, was summoned by her father, Admiral Garrick Versio, aboard the Eviscerator in orbit of Vardos to receive her next orders. She received her orders via a Messenger droid carrying the Emperor's last command, though she was suspicious of what Operation: Cinder entailed. Inferno was dispatched to an Imperial shipyard above Fondor to ensure the safety of Moff Derrek Raythe, who was in the process of acquiring and transporting satellites essential to Operation: Cinder, although Inferno was not informed of the target of the satellites. During this time, the Rebel Alliance launched an assault on the Dauntless, but their MC80 Star Cruiser flagship was ultimately destroyed by Inferno.
After climate-disruption arrays were deployed to planets in Operation: Cinder, elite units of TIE series craft—including the 204th Imperial Fighter Wing, otherwise known as Shadow Wing—were deployed to ensure all below was ruined. Other tactics would see use in Operation: Cinder, including the deployment of the Imperial Navy and Imperial Army.
After securing Raythe's satellites and destroying the Emperor's Observatory on Pillio, Iden and Inferno Squad came back to Vardos, an Imperial stronghold and the homeworld of the Versio family. Upon their arrival, they noticed the experimental satellites they had protected at Fondor deployed in the planet's upper atmosphere along with the Dauntless itself, the flagship of Raythe. Now aware of their target, Iden confronted her father aboard the Eviscerator, furious that their own homeworld was a target of Operation: Cinder despite its loyalty to the Empire. In response, Admiral Versio stated in his point of view of Operation: Cinder that, for the greater good of the Empire, Vardos and other worlds had to be sacrificed so that the utter fear and brutality would prove beyond a doubt to the galaxy that the Empire was still in charge. Garrick then ordered for the satellites to be activated, spawning massive electrical storm systems within minutes. Whilst the storm systems laid waste to the planet surface, anti-air batteries shot down any non-Imperial ships attempting to leave in order to contain them on Vardos.
Iden and Inferno Squad were ordered by Garrick to extract Protectorate Gleb alone from the planet and bring the Aqualish to him. However, at the Archive in Kestro City, Iden and Del Meeko attempted to bring along other civilians with them to transport them off world. Agent Gideon Hask, refusing to disobey Garrick's command, attempted to prevent this from happening, but was unable to stop the civilians from fleeing to the Corvus. Iden claimed that the Empire's job was to protect civilians from things like Operation: Cinder; Hask responded that this was the "new Empire," prompting Meeko to state that he sought no part in this "new Empire" and would follow the orders of his commanding officer, Iden. When Hask refused to lower his blaster and aimed it at Iden, she shot him first in his leg. Hask returned alone to Garrick with Gleb and a Rodian while Iden and Del escaped aboard the Corvus with their crew, jumping into hyperspace to the Outer Rim Territories. There, they decided to formally surrender themselves to the Rebel Alliance.
Shortly after the Battle of Endor, Captain Lerr Duvat of the Star Destroyer Torment received a visit from a Messenger droid, delivering the Emperor's final directive: to initiate Operation: Cinder without delay. Twenty days following the Battle of Endor, Duvat's Star Destroyer was redeployed to Naboo and launched satellites into orbit to establish a climate disruption array. This array was employed to generate massive hurricanes and electrical storms across the planet. By the time the array's power reached twenty percent efficiency, three class-five hurricanes were already formed—with another dozen forming. As fires, flooding, and chaos ripped across the surface of the planet, Lieutenant Shara Bey of the Alliance to Restore the Republic—who accompanied Princess Leia Organa to Naboo, where Organa rallied the support of Queen Sosha Soruna in establishing the New Republic—realized that the satellites had to be behind the phenomenon. The only means Naboo had of fighting back was to scramble starfighters to destroy the satellites.

Bey was placed in command of the mission, with Organa and Soruna accompanying her. The Emperor demilitarized Naboo many years earlier, but a few N-1 starfighters remained in storage from the Battle of Naboo decades earlier. Once in orbit, Bey destroyed a number of the satellites while Organa and Soruna dealt with TIE fighters dispatched from the Torment. The three pilots were outgunned against seventy-two TIE fighters and were nearly killed until General Lando Calrissian arrived with a Rebel fleet, along with Danger Squadron, whose newest members were Iden and Meeko, former Imperial commandos who provided key intel to the Alliance about Operation: Cinder. The Alliance had also gathered intelligence of Operation: Cinder during a raid at an Imperial Security Bureau complex at the Wretch of Tayron, allowing them to move their forces to Naboo in time to help save the planet.
Though Danger Squadron was able to destroy the satellites and cripple the Star Destroyer in orbit of Naboo, surviving Imperial forces, following standard protocol, evacuated to the nearest safe haven: Theed, the capital city of Naboo. There, Danger Leader Shriv Suurgav, Iden, and Meeko met up with Organa, who covered Meeko as he repaired Theed's defenses. Once rebel forces were inside the royal palace, the defense system was activated, sending an ionic disruption across the city that disabled all blasters and starfighters, forcing the remaining Imperials to surrender. Afterwards, Organa confronted Iden and Meeko over the damage that they had done to the Alliance in the past. Iden apologized on behalf of them, and wished to continue to fight with the Alliance in order to continue the fight against Operation: Cinder and the new Empire. Organa complimented them on being images of hope for the galaxy, and formally welcomed them to the New Republic, which Inferno Squad was integrated into.
Following the Battle of Endor, Governor Ubrik Adelhard imposed an Iron Blockade on Burnin Konn, disseminating propaganda that falsely claimed the Emperor's death reports were untrue. Consequently, underworld operatives on Burnin Konn initiated their own uprising against the Empire, seeking alliances with other worlds affected by the blockade. Approximately three months after the Battle of Endor, the Empire dispatched Valin Hess and at least one division to carry out the operation on the planet. Hess arranged to deploy Imperial forces to plant plasma bombs within the generators that harvested energy from the geothermal reactors that powered most of the planet. This would usually result in collapsing whole cities as a result of destabilizing the plate tectonics of the world. During their operations, one of the cities named Chakonnis attempted to resist, coming in the form of civilians who sought to defend their homes. In response, Valin Hess ordered the city to be wiped out, an action which caused the loss of many civilians and his entire division, the latter of which numbered somewhere between 5,000 to 10,000, a staggering loss carried out within moments. Among the attack's survivors were a sniper named Migs Mayfeld and Hess himself.
Three months after the Battle of Endor, the Empire persisted in executing Operation: Cinder across numerous worlds. A dozen other worlds were targeted or still being targeted, including Burnin Konn, Candovant, Abednedo, Commenor, Nacronis, and Senthrodys, which endured the shattering of its crust. The Republic was able to determine the purpose of many of these attacks, though they found that the Empire's motivations behind others were less clear. Nonetheless, Republic forces were able to save untold numbers of civilians as a result of combating the Imperial operation. Despite that, it would still be many months until the war came to an end, with Admiral Gial Ackbar and General Crix Madine seeing no end to hostilities with the Empire in the short-term.

Naboo was once again targeted by the Empire during the Invasions of Naboo in an attempt to eliminate New Republic forces stationed on the planet. However, the Republic successfully thwarted these attacks, mirroring their response to Operation: Cinder. The final stage of the Contingency unfolded in 5 ABY when New Republic forces launched an assault on the Empire, assembled on Jakku by Counselor Gallius Rax, during the Battle of Jakku. Harnessing the power of ancient Sith artifacts buried beneath the surface, Rax aimed to execute the ultimate component of Palpatine's Contingency by corrupting the planet's core and life essence with the dark side, thereby obliterating the desert planet and annihilating both Imperial and Republic forces, thus crippling both sides. However, Grand Admiral Rae Sloane thwarted the Contingency, driven by her desire for retribution against Rax for his removal of her from power. She killed Rax, though in his dying breaths, he urged Sloane to regroup with select Imperial officers and loyalists in the Unknown Regions and begin the Empire anew.
Sloane's actions undermined Operation: Cinder. Nevertheless, by taking Rax's place as leader of the Imperials who escaped into the Unknown Regions, she became part of the foundation of the First Order. As a result, the Emperor's Contingency proceeded according to his plan to return to power.
The Republic emerged victorious during the battle and signed the Galactic Concordance with the Empire's Grand Vizier, Mas Amedda, bringing an end to the Galactic Civil War. However, in the Unknown Regions of the galaxy, Sloane, Brendol Hux, and other Imperial loyalists formed the First Order, seeking to one day reclaim the Imperial legacy as they plotted their return to power.
On Morak in 9 ABY, Valin Hess would offer a toast to Operation: Cinder with Din Djarin and Migs Mayfeld, who were both undercover, unbeknownst to Hess, infiltrating the Imperial base. He noted that the rhydonium Mayfeld and Djarin had brought in would actually help the Imperial Remnants carry out operations even bigger than that of Operation: Cinder. Mayfeld, having fostered regret and misgivings about his role in Operation: Cinder decided to shoot and kill his former superior then and there, which forced him and Djarin to fight their way out of the base and eventually leading Mayfeld to decide to detonate their rescued batch of rhydonium causing a chain reaction of explosions that brought forth significant damage to the base.
Decades after the implementation of Operation: Cinder, the bombardment campaign's effects continued to be felt. Kestro on Vardos frequently rained with atmospheric ash at the start of the First Order-Resistance War.
Operation: Cinder made its debut in the second issue of the Marvel comic book series Star Wars: Shattered Empire, authored by Greg Rucka, and released on October 7, 2015.
When asked, Star Wars: Uprising writer Alexander Freed confirmed that there was a strong possibility that the video game would have portrayed the events of Operation: Cinder had its production not been prematurely terminated.