Bok

"If we're late, [the Elites]'ll take our heads. And our kin will take yours, gas-sucker."

- Bok to Yayap, disobeying the Grunt's precautions.

Bok was a Kig-yar soldier who fought in the Battle of Installation 04 during the Human-Covenant War.

Battle of Installation 04
Bok was stationed aboard the crash site during the events on Installation 04. After a raid by Marine Shock Troopers, 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 didn't infiltrate the vessel at all.

He was placed under the command of Yayap, a Special Operations Grunt, after the Unggoy arrived at the site with Zuka 'Zamamee, following a failed battle at the Alpha Base. He did not like the Unggoy soldier, calling him a "Gas Sucker". Nevertheless, he complied with Yayap's orders because he had no choice. He, along with Jak and Yeg tried to make Yayap's life difficult anyway.

Death
One of the containers he opened contained a group of Infection Forms and Combat Forms. As he opened the container, they jumped out and infected him, but the other Jackals and Yayap killed all the Flood and the infected Bok before they could cause any harm.