Halo Alpha
Halo Alpha

ONI Section Three, or ONI Section 3,[1] was a subdivision of the Office of Naval Intelligence.


In 2512, Hieronymus Stanforth became the head of Section Three. During his administration, Section Three was at its busiest. Project MJOLNIR, Project GUNGNIR, and the SPARTAN-II Program were all created during his tenure. He would then retire from this position to fulfill a more active frontline role in 2530.[2]

Human-Covenant war[]

ONI Section Three was one of the first divisions of ONI to interact with the Covenant. Agent Jilan al-Cygni would investigate and participate in a skirmish over Harvest and fight in the First Battle of Harvest.

A few months later, Hieronymus Stanforth ordered the acquisition of a Covenant Starship to gain better insight into the Covenant's technology. SPARTAN-II soldiers and UNSC prowlers were to conduct the mission. The ship was then to be given to Materials Group.[3]

In 2532, several SPARTAN-II augmentation chemicals were routed to Section Three labs on Algolis, Ariel, and Meridian without Dr. Catherine Halsey's approval.[1]


At some point after the war, Section Three began to develop a simulation to help train Spartans and science teams going to Halo rings. This was called Project BLACKBALL.[4]


Section Three's main responsibility is special projects for use within the UNSC. With that, it also oversees all of the various groups who do this.[5] This has lead to the creation of many assets such as the NOVA project, the MJOLNIR Program, and many other "black ops."[6]


Though a few of Section III's programs are well known and celebrated for their success, the Marines and top brass of the UNSC treat most with contempt. This is especially true of the Spartans, who are regarded as "freaks" by some Humans.






Unnamed Facilities[]

Section Three had facilies on Meridian, Algolis, and Ariel.[1]


  • In the epilogue of Halo 3: ODST, the lighter carried by Avery Johnson bears an Orion logo, with Section Three's name on it, although this is difficult to see in-game.[8]