From Halopedia, the Halo wiki
At the conclusion of the Human-Covenant War, Ferko was one of many Jiralhanae present in Truth's fleet, which engaged in the Battle for Earth and the later Battle of Installation 00. Ferko was ultimately one of the many survivors of the battle, and found his way into joining the loyalists led by Dhas Bhasvod. Along with the other loyalists, he would remain stranded on Installation 00 for seven years.
Second Ark Conflict
By 2559, Ferko served Bhasvod's forces as the pilot of a Seraph fightercraft. Eventually, he was deployed by Bhasvod to investigate the apparent defection of the Ferrets from the Keepers of the One Freedom to the forces of UNSC Spirit of Fire. Ferko was responsible for a bombing run against the site of a laser emitter.
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