The Office of Naval Intelligence (usually referred to as ONI) are a division of the United Nations Space Command that operate separate of other branches of the UNSC, and handle human communications within the universe, a large amount of confidential information, a number of top secret operations and projects, and pro-UNSC propaganda. Almost all of the work ONI carry out is highly classified, and despite ONI being an intelligence authority they have a considerable military presence.
ONI is split up into the UNSC Prowler Corps, the ONI Signal Corps, and Sections Zero to III. The UNSC Prowler Corps handles all UNSC Prowler-class ships, a class of stealth ships used for infiltrating enemy computer systems and gathering vital data. The Prowler Corps would at first appear to be a direct division of the UNSC, however the Prowler-class ships are used solely by ONI, suggesting it is much more likely to be a division of ONI. The ONI Signal Corps is a division of ONI tasked with broadcasting fake radio signals across a number of empty areas of space to confuse Covenant to the whereabouts of human colonies.
Almost nothing is known about Section Zero due to it dealing with the most highly classified of ONI data and operations, however it is believed the section keeps the records of Project ORION (also known as the Spartan-I project) and may be responsible for detecting and deleting illegal computer programs. Section I is the main division of ONI and often works closely with the rest of the UNSC. Section II is in charge of propaganda, handling communications between human colonies, and keeping secret any information which could lower human morale during the Human-Covenant War. Section II are particularly notable for releasing information on the Spartan-IIs to the public in an effort to raise morale, and declaring that Spartans should always be listed as MIA when they died to keep alive the myth that Spartans never die. Section III is the division responsible for ONI's secret projects, including the Spartan-II project and Project Mjolnir. There are a large number of sub-cells of Section III, the most notable of which is Beta-5, the people behind of the Spartan-III project.
Major Roles in Halo Games
Halo 3: ODST Campaign
Halo 3: ODST focuses largely around an ONI operation. After an AI known as the Superintendent, located in New Mombasa, Earth, detects seismic activity from a Forerunner artefact and Covenant invade the city, ONI Section I operative Veronica Dare requests an Orbital Drop Shock Trooper squad to aid her in recovering the Superintendent and it's vital data before the Covenant. The true purpose of the operation is kept secret from the ODST squad and they are told they are part of a mission to infiltrate the Covenant Cruiser over New Mombasa and assassinate the Prophet of Regret. As the ODSTs and Dare make their drop into the city the cruiser enters slipspace, causing a slipspace rupture which knocks the ODSTs' pods off-course and severely jeopardises the mission.
At one point in Halo 3: ODST squad members Michael Crespo and Taylor Miles make their way to ONI Alpha Site to group up with a number of New Mombasa Police Department officers. In an effort to stop the Covenant entering the ONI Section II headquarters they blow up the single bridge leading to the facility, however the Covenant manage to infiltrate the building and Crespo and Miles are forced to fight them off, before escaping and blowing up Alpha Site in order to stop the Covenant capturing the data from the facility. Eventually the entire ODST squad manage to regroup, they discover the true purpose of their mission and the data from the Superintendent is recovered, proving to be highly useful in the second battle of Earth.
Halo: Reach Campaign
In Halo: Reach the ONI base on Reach known as Sword Base plays a major role. At one point the base comes under attack from a Covenant Corvette and it's forces, however Noble Team, along with a group of other UNSC forces are able to drive the Covenant back. After the Covenant begins their full attack on Reach they manage to infiltrate Sword Base, discovering it to be constructed on top of a Forerunner artefact. Noble Team return to the facility and eliminate the Covenant forces who had seized the base before being contacted by Doctor Catherine Halsey. They discover that Halsey has a secret base far below the facility where she has been studying the Forerunner artefact. Halsey puts Noble Team in possession of the AI Cortana who has vital data on the Forerunner artefact (data which Halsey believes will win the war against the Covenant) and instructs them to deliver Cortana to the ship UNSC Pillar of Autumn. Spartan-312 of Noble Team succeeds in delivering the data, however Sword Base is destroyed.
In the Halo 3: ODST firefight mode one of the maps available for play is ONI Alpha Site, and in the Halo: Reach multiplayer one of the available maps is ONI Sword Base.
- ONI's name is likely a reference to the Bungie game Oni.
- One of the tracks on the Halo 3: ODST soundtrack is titled 'The Office of Naval Intelligence'.
- The Office of Naval Intelligence is currently a real-life organisation which exists as part of the US Navy.
- ONI's motto is 'Semper Vigilans', meaning 'Always Vigilant'.