- “Good thing our file leader kept 'em in line.”— Jak, referring to Yayap
Jak was a Covenant Jackal stationed aboard the UNSC Pillar of Autumn crash site during the Battle of Installation 04. After a raid by ODSTs led by First Lieutenant Melissa McKay, he was assigned to inspect and haul cargo coming into the crashed vessel for use by the Covenant who occupied it. This was to make sure that Flood did not infiltrate the vessel.
He was placed under the command of Yayap after the Unggoy arrived at the site following a failed invasion of Alpha Base. He did not like the Grunt, calling him a "Gas Sucker." Nevertheless, he complied with Yayap's orders because he had no choice. He, along with Bok and Yeg tried to make Yayap's life difficult anyway.
After Bok was killed by a group of infection forms hiding in a cargo pod, Jak suddenly became much more respectful of the Unggoy, stating: "Those damned Gasers nearly got us all killed. Good thing our File Leader kept 'em in line." It is unknown what happened to Jak, though, it's likely that he was killed when John-117 detonated the Autumn's engines and thus destroyed Installation 04. It is also possible that he escaped along with a large number of other Covenant.
- Halo: The Flood (First appearance)