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Terminal.png This article, OPERATION: OCTOBER, was written by Kojima sama. Please do not edit this fiction without the writer's permission.
"You are accused of high treason and anti-UEG activity, this tribunal finds you guilty and sentences you to be shot"
―OPERATION: OCTOBER archives, 23/1456 keyword matches


OPERATION: OCTOBER known within ONI as ‘the bad years’ was an extensive internal investigation conducted by the Office of Naval Intelligence in late 2556, soon after the ascension of Serin Osman to the position of Commander-in-Chief of the Office of Naval Intelligence . It was the prevailing belief among a number of ONI officers and bureaucrats that the post-war atmosphere would necessitate a radical change in the organization if it was to maintain its power, these officers had grown worried that peacetime investigations into their activities, such as the one attempted by Benjamin Giraud, would inevitably reveal the various secrets of the organization and urged the sacking or demotion of those responsible for various classified wartime projects. When Osman refused, these officers and agents enacted OPERATION: OCTOBER, an effort to jail or execute ONI officers involved in morally dubious acts. Lead by an up and coming ONI functionary codenamed ARTEMISIA, OCTOBER would send almost immediately send shockwaves throughout ONI, and ARTEMISIA would be joined by other higher ranking ONI agents and officers, such as CODENAME: ODYSSEY, CODENAME: KARACHI, and CODENAME: GEORGIA.  While such an endeavor would appear on its surface to be a rare act of altruism on the part of ONI, in actuality OPERATION: OCTOBER was largely a power play by a number of ONI agents, fabricating evidence to have rivals executed or jailed. It is also speculated that many victims of OCTOBER also had incriminating evidence on its directors, and the operation was only ordered to cover their own tracks. It has proven exceptionally difficult for ONI to determine the impact of OCTOBER on its ranks, but estimates suggest anywhere between ten to twelve thousand ONI agents were jailed by OCTOBER, approximately seven hundred of these being high ranking officers. Another estimated three to five thousand were killed, either in combat or executed, approximately two hundred being high ranking officers. It is still uncertain how much of the testimonies, evidence, and confessions produced during OCTOBER are genuine.

With how closely intertwined UNSC special forces and ONI were, violent resistance from OCTOBER’s targets would not be uncommon, and in some cases resistance to arrest was enough evidence to warrant a guilty verdict from OCTOBER’s agents. Many Section Three and NAVSPECWARCOM units were caught up in OCTOBER’s fighting, both for and against it. Various mercenary companies were also brought into the fight as deniable operations or private security, with Hannibal Weapons Systems providing additional support to both CODENAME: ARTEMISIA’s faction and the ones he opposed. At least one SPARTAN-III was noted to have participated in a military action under OCTOBER’s jurisdiction, with an indeterminate number of SPARTAN-IVs participating on both sides of OCTOBER. On occasion, UNSC Marine and Army units would also be used in the fighting in OCTOBER.

While Serin Osman was quite acutely aware of the civil war raging in her own agency, she had done little to stop its outbreak. Osman and OCTOBER held several mutual enemies, and the operation had her tacit support so long as it did not target her allies or assets. It was this fear of retribution from Osman that kept most of OCTOBER in check, and prevented the agency from dissolving wholesale during the course of OCTOBER.



"It's not a matter of if the public finds out, it's a matter of when. All it takes is one botched cover-up. With what's in that folder, are you comfortable taking that chance?"

In September 2556, a number of intelligence analysts within ONI’s Section Zero, were put to the task of conducting a thorough internal audit of the other three Section’s activities from the start of the 2500 to the modern day. Led by CODENAME: ARTEMISIA, this group had delved through top secret records and files, uncovering programs and operations conducted without Section Zero’s knowledge. Some of these were intentionally hidden from other ONI Sections, while others were simply forgotten about during the chaos of war. Before long, CODENAME: ARTEMISIA and his colleagues had realized that they had developed a relatively extensive list of the other Sections' atrocities and wrongdoings, some of which Section Zero was totally unaware of. Fearing that a particularly devoted civilian or independent investigatory body could find evidence of these crimes, ARTEMISIA’s team had advocated for the total destruction of all incriminating evidence and a nonlethal removal of all associated operatives from their posts.

Serin Osman had discussed this course of action with her Section Chiefs, and ultimately had decided against this, believing the records and expertise of the scientists, officers, soldiers, and spies involved to be too valuable to discard. She was also fully convinced in Section Two’s ability to discredit any potential investigation into the Office, as shown by their response to Benjamin Giraud’s efforts. CODENAME: ARTEMISIA and his team were left unsatisfied with this, and moved to take action without direct authorization after the team gathered a support base behind them. Osman had soon become wary of this, viewing it as a power-play from old guard officers seeking to usurp her. However, these thoughts were dispelled when the OPERATION: OCTOBER was quietly initiated.


CODENAME: ARTEMISIA knew OCTOBER’s first target would have to be carefully selected, necessitating one that would not upset the established order too severely. Additionally, the target had to be unquestionably morally reprehensible to dispel any notions of OCTOBER being motivated by political ambition. OCTOBER’s leadership had decided on CODENAME: ATLANTIC, an Insurrection era Section Three branch officer responsible for leading OPERATION: CENTIPEDE, an effort to destroy or subvert criminal groups associated with the Insurrection. ARTEMISIA’s audit had found that ATLANTIC had appropriated funds used in CENTIPEDE for personal use, profited from drug and human trafficking, and intimidated local police organizations into ceasing their investigations against him, resulting in the ‘disappearance’ of hundreds of UNSC aligned police officers across two worlds. By the end of the Human-Covenant War, ATLANTIC had developed a widespread support network, both within the Office and with the criminal underworld. This would complicate things for OCTOBER, as ATLANTIC’s solid support base would stonewall any bureaucratic attempt to have him removed, leaving violence as their only option. ARTEMISIA had enlisted CODENAME: ODYSSEY and her unit of Section Three operators to assist, aiming to raid ATLANTIC’s compound on Tribute. Code named OPERATION: SATURN RISE, the assault on the compound was intended to rapidly kill or capture ATLANTIC rather than engage his forces. A lifelong paranoiac, ATLANTIC’s compound was heavily fortified and staffed by a full company of ONI operators and another company of mercenary troops. Unconfirmed reports of SPARTAN-IVs guarding the compound had also filtered up to ARTEMISIA and ODYSSEY, resulting in reservations about the assault.

"There's more wealth in there than some museums. He deserves none of it."
―CODENAME: ODYSSEY briefing ONI troops prior to the raid

ATLANTIC’s was as luxurious as it was well defended, with the branch officer profiting handsomely from his dirty dealing during the Insurrection. The house itself measured a full square kilometer in surface area, with four floors and a basement. The compound was also filled with various taxidermied big game animals, ranging from Earth based species to alien fauna from human colony worlds, rumored to have been hunted by ATLANTIC himself. Various works of art had lined the wall, from modern masterpieces to works made in human antiquity. After the Human-Covenant War and following the thaw in Human-Sangheili relations, ATLANTIC had also acquired a variety of Sangheili artwork through dubious means. Thanks to the chaos of the Human-Covenant War, and ATLANTIC’s agents’ own meddling, most financial records and investigative inquiries into his spending were destroyed. This had also proven a problem, as OCTOBER’s leaders worried that what evidence they had would not be enough to incriminate him. Thus, the second objective of the raid, the seizure of any documents or items that would prove ATLANTIC’s corrupt behavior. CODENAME: ODYSSEY had also proposed using recovered items to fabricate evidence.

A guard outpost close to ATLANTIC's compound.

Aside from the compound’s defenses, four outposts were placed around the ATLANTIC’s, each with extensive sensor arrays, alarm systems and a four barreled anti-aircraft gun. This had complicated infiltration, as any vehicle would likely be detected well before CODENAME: ODYSSEY would be able to deploy her troops; two full companies of NAVSPECWARCOM operators codenamed SPRITE and BLUEBELL. Instead, ODYSSEY opted for an infiltration on foot using the tall grasses of the savanna surrounding the compound to conceal their approach. When SPRITE approached the northwest compound, they encountered and quickly surrounded the mercenaries within. Intending to minimize their footprint, SPRITE had intimidated and bribed the mercenaries to stay within the compound, seizing their weapons and subverting the security systems before sealing them inside. A general all-clear was continuously broadcast, ensuring that the rest of the defenders were unaware of the situation, allowing BLUEBELL to make their infiltration into the compound. BLUEBELL was ordered to keep a perimeter around the compound, maintaining sensor jammers and sabotaging exterior sensor systems. While many of ATLANTIC’s operators within the compound were none the wiser, ATLANTIC himself was not so easily fooled, and had kept an as of yet unidentified SPARTAN-IV by his side at all times. Fully confident in the capability of his defenders, ATLANTIC went about the coordination of his underworld trade as normal.  

Members of SPRITE during the raid on ATLANTIC's compound.

SPRITE and elements of BLUEBELL would breach into the compound, promptly engaging the guards within the compound. The firefight had spread throughout the compound as ODYSSEY’s troops had combed the area for ATLANTIC, growing more intense as more units had gotten involved. Both sides in the fight had sustained casualties early on in the fight. The other mercenary platoons were led away by decoys and signals misdirection, with only a handful of mercenary units falling back to the compound to reinforce the defenders, but these were intercepted by BLUEBELL.

Ultimately, ATLANTIC would be killed in the crossfire of the raid, greatly simplifying the case against him. He would posthumously be convicted of high treason and corruption and have all awards and medals stripped


"The more dead monsters to our name, the more palatable our cause. I can only hope the others realize this sooner rather than later."
―Excerpt from CODENAME: ARTEMISIA's diary.

Following the success of SATURN RISE, OCTOBER’s existence became more widely known among the ranks of ONI, despite the measures taken to keep the operation secret. This would prove to be both a boon and a bane for the agents facilitating it. Many other ONI agents from all of the Office’s sections were sympathetic to the cause, for various reasons ranging from idealists with a genuine desire to see justice delivered to opportunists looking to remove rivals or further their position in ONI. Serin Osman was impressed by the efficiency of the operation to remove ATLANTIC, and surreptitiously funneled funds, materials, and manpower in support of OCTOBER’s goals. Serin had additionally ordered the total erasure of ATLANTIC’s existence from both public and private records, looking to intimidate any who might oppose OCTOBER’s goals. However, knowledge of OCTOBER would result in the individuals it targets taking preemptive action against it. In one notable incident, two senior OCTOBER analysts were poisoned with ricin on their way to an office, resulting in the death of one and the hospitalization of the other. A shooting incident against OCTOBER agents had taken place outside of one of their safehouses, leaving three OCTOBER field agents dead. These attacks against OCTOBER associated staff would continue into the middle of 2557, where extensive enhanced security protocols would be fully rolled out and several opposition operatives were captured and interrogated.

While many opponents to OCTOBER made their moves in the wake of SATURN RISE, others not directly targeted by the operation would also act to protect themselves. Operatives connected with criminals, minor functionaries, and simple paranoiacs would seek to hamper the progress of OCTOBER, primarily through bureaucratic stonewalling and misdirection, keeping themselves beneath the notice of OCTOBER for the time being.

CODENAME: ODYSSEY, executive officer of OCTOBER.

There was much debate over who the next target of OCTOBER should be, with the upper echelons of OCTOBER’s leadership descending into factionalism over this issue. One group, led by ARTEMISIA had urged to continue the purging of presumed war criminals, hoping to present his project as unquestionably beneficial to ONI and humanity at large. Political opponents to ARTEMISIA had accused him of lacking evidence for his new list of targets, claiming that this new list was merely a plot to consolidate more power under OCTOBER and thus his own control. The second faction, led by CODENAME: ODYSSEY had developed a list of agents and officers who had ordered the attacks against OCTOBER in recent months. Through extensive infiltration of enemy personnel networks, ODYSSEY’s faction had demanded that action be taken against several high ranking officers within Section 3 and 0 before the enemy strikes OCTOBER again. Additionally, ODYSSEY had claimed that OCTOBER had also been infiltrated at several levels, and that the operation must identify and eliminate these spies by any means necessary. However, this plan had also ran afoul of a segment of OCTOBER’s leadership, accusing ODYSSEY that she too was attempting to centralize power under her, and her plan merely an attempt to facilitate this by removing anyone her faction deemed to be traitors.

OCTOBER was paralyzed by this factionalism until 2558, when the leadership decided on their next move.

Phase Two

ONI Alpha Site served as OPERATION: OCTOBER's headquarters.

Ultimately, ARTEMISIA would relent on his stance of continuing offensive operations against OCTOBER’s targets. Outwardly this was a move to assuage the concerns of his rivals, to reassure them that his actions were only meant for the good of the office and the operation rather than for his personal gain. ARTEMISIA had presented himself as someone who cared for the safety of the agents under his command, and thus had prioritized the removal of any infiltrators who might threaten them. ARTEMISIA had proposed a compromise between himself and ODYSSEY, splitting OCTOBER’s resources into two components, one for action against external hostiles lead by ARTEMISIA and one for internal security lead by ODYSSEY. While this was presented as an olive branch between the two executives, ARTEMISIA had implemented a measure to keep ODYSSEY in check. ARTEMISIA had greatly limited ODYSSEY and her faction access to OCTOBER’s resources and manpower, ensuring that a power grab would be exceptionally difficult to execute. Additionally, this separation was also intended to separate ODYSSEY from ARTEMISIA, ensuring that whatever failures she and her agents had endured would be laid square at their feet. It is likely that ODYSSEY was aware of this, but had little choice but to comply or else worsen the factionalism within the operation. ARTEMISIA and his operatives would select their next target, a Section 3 scientist known as CODENAME: APHID. APHID was a lead scientist in nearly all of the biochemical products used in the various supersoldiers programs employed by the UNSC. Contact with APHID was lost several weeks after OPERATION: TORPEDO resulted in the near total annihilation of Beta Company’s SPARTAN-IIIs. APHID was targeted for two reasons, over fears that he could divulge top secret information to external sources, and to bring him to justice over a number of medical experiments conducted on UNSC military personnel and civilians prior to the finalization of the battery of augmentations that would be applied to the SPARTANs. The operation to eliminate APHID was codenamed ANCHOR FALL.

"Can't speak straight to anyone anymore. Not 'less you wanna get booked for seditious sentiment by someone who wants your job. "
―Anonymous ONI Agent

ODYSSEY’s task was somewhat less clear cut compared to her comrades under ARTEMISIA. With their work codenamed WHITE PALACE, ODYSSEY was given the broad task of counterintelligence and operational security. WHITE PALACE’s enemies were far from amateurs, and apart from being aware of their existence, ODYSSEY and her assets had little further knowledge about them. Extensive internal investigations were conducted, interrogations and interviews of all recent acquisitions into OCTOBER. Smart AI were requested to assist in signals intelligence and decrypting messages. The investigations were so thorough that critics of WHITE PALACE had accused it of being an effort to hamper it. It took several more months before leads had started to crop up. Hundreds upon hundreds of arrests were made following this, with a close to an estimated twelve hundred ONI operatives jailed on charges of sedition and treason. Approximately half would not be acquitted of these charges until officially OCTOBER concluded in 2563. A number of these arrests uncovered legitimate infiltrators and moles, one hundred and thirty three of which were executed following their convictions.


"How many of ours need to die skulking around in the dark before we let them accomplish our objectives?"
―OCTOBER Committee #556

OPERATION ANCHOR FALL had taken into consideration many lessons learned from SATURN RISE, and it utilized new technologies and equipment developed after the success of SATURN RISE. ANCHOR FALL operatives had been equipped with active camouflage armor systems and superior sensor jammer technology sourced from Sangheili devices. There was much debate as to how much subtlety was appropriate in operations of this nature. Some had argued that stealth was unnecessary due to the substantial security resources targets would likely have. These agents had argued that the overwhelming force was preferable, as ONI also had the propaganda resources to properly cover up their operations from public scrutiny, or even present their actions as morally good in the eyes of the UNSC public. On the other side of the aisle, agents had claimed that subtle action was still preferable as it had reduced the costs of operation, as OCTOBER would no longer need to invest in expensive cover-ops and falsified news. The more aggressive faction within OCTOBER would win out over their counterparts, leading ANCHOR FALL being a ‘louder’ mission.

A Mantis of STRIDER preparing to assault the Justicia campus.

CODENAME: APHID was identified to be an executive within a minor biotech company Justicia Solutions, responsible for developing genetic and pharmacological treatments for a variety of recently discovered and extant diseases. While the company was relatively small, it had boasted a contingent of mercenaries from several arms contractors. Covert observations of APHID showed that he rarely left company holdings, which were universally well defended by these mercenaries. These troops had proven to be well equipped with heavy weapons and armor, even boasting a number of Pelicans and Mantii. The troops staffing Justicia were almost universally veterans of the Human-Covenant War, with several years of combat experience between them. Rumors of the defenders being somehow enhanced beyond human capabilities had abounded, among field agents but could gather little information to corroborate this.

The operation would take place on the colony of Luyten, the campus of Justicia was far from the population centers of the colony allowing the troops led by ARTEMISIA additional operational freedom. Unlike SATURN RISE, the pace of the operation was far slower, with several days of on site observation and planning before any military action was considered. The greatest source of concern were the extensive armor and air assets available to the mercenaries, while the troops under ARTEMISIA were equipped with weapons to deal with these obstacles, the mercenaries were relatively conservative with these assets, keeping them within campus limits and thus preventing their preemptive destruction. Luckily for the troops of OCTOBER, they had the element of surprise on their side. APHID was never made aware of OCTOBER, let alone that he was a target of the operation. As such, security was relatively lax despite OCTOBER having a company and several Mantii of their own within five kilometers from the campus. The infantry company was codenamed CENTURY and the Mantii company STRIDER. After nearly two weeks of observation and reconnaissance ANCHOR FALL had begun in earnest with a rocket strike on outlying mercenary positions, almost immediately throwing them into disarray, preventing them from repelling the push into the campus by ONI troops.

"Must be gettin' paid twenty times more than us with the way they're fighting."
―Anonymous CENTURY operator

Despite the sudden rocket attack on the Justicia campus, the mercenary troops managed to regroup and eventually respond to the ONI assault on their positions. While many of their fortifications were destroyed in the initial bombardment, many of their automated defenses were still operational, leading to the ONI advance stalling out as they attempted to penetrate deeper into the corporate campus. The presence of non-combatants in the area had complicated the situation for both factions, and the ONI commanders in charge of the operation had debated whether to continue the bombardments. CENTURY and STRIDER had sent any non-combatants back behind their lines, and the Justicia aligned mercenaries had ordered all corporate staff into hardened bunkers. With those concerned dealt with as best as possible, ONI forces had continued their rocket strikes from their Mantis platforms, suppressing enemy troops while more precise guided missile strikes had destroyed automated turrets and leveled pillboxes.

CENTURY had managed to secure a foothold in the center of the campus, but even with these significantly softened defenses the mercenary forces had managed to hold them off from the central building, where APHID and his staff were preparing to evacuate along with their work. A stalemate had settled in the Justicia campus, and the mercenary commander had urged APHID to leave and allow the mercenaries to destroy any remaining evidence; but due to a lack of understanding of the situation or arrogance APHID had insisted that the evacuation wait until all materials relevant to his research was ready to be moved.

Mercenary Pelicans sortie to intercept ONI Mantii exoskeletons.

This stalemate would persist for several more hours, with neither side willing to make the first move in fear of sustaining heavy casualties. CENTURY took this lull in the battle to regroup and perform some impromptu fact-finding, recovering left behind drives and server nodes for evidence in the case against APHID. The stalemate was broken by the mercenary forces getting their Pelicans airborne, targeting the ONI Mantii in an attempt to push back their advance. STRIDER had responded with MANPADS fire, downing several of them but not before the mercenaries disabled four of STRIDER’s nine Mantii.

Seizing upon this advantage, CENTURY had pushed forward under cover of their exoskeletons. After four hours of intense firefights and heavy casualties inflicted on the mercenaries, the remainder of the opposing force had chosen to surrender to ONI. Breaching into the final compound, CENTURY had encountered APHID’s trump card, ONI operatives loyal to him who were clearly under the effects of some sort of rumbledrug. The close quarters scenario had worked in APHID’s troops’ favor as they tore through the incoming ONI troops with relative ease, suffering none of the drawbacks typically associated with rumbledrugs. These enhanced troops were dealt with by autocannon from STRIDER’s Mantii. APHID was interred and brought back for interrogation.

While ANCHOR FALL was a relative success ONI had paid a relatively heavy toll for it, suffering nearly a hundred dead and two hundred wounded. The cover-up work had also taken up a significant amount of resources, disguising the operation as a mission against Insurrectionists. Using the evidence gathered during the operation it was also determined that APHID was intending to market biotechnical military augmentations to non-governmental entities.