Siege of Qikost
From Halopedia, the Halo wiki
The Siege of Qikost was an ancient and protracted civil conflict fought by the Sangheili, on their homeworld's moon Qikost. Little is known of the war, though during the fighting Warlord Nakada 'Zadum was able to craft and deploy the now-standard Elo'Nakada-pattern concussion rifle for the first time.
- ^ Halo Encyclopedia (2022 edition), page 296