From Halopedia, the Halo wiki
During the battle of Algolis, a UNSC firebase came under assault by Covenant forces and Taylor and his fellow marines faced a suicidal wave of forty Jiralhanae warriors. In the ensuing skirmish, Taylor was left as one of the few surviving marines after the Jiralhanae's ruthless attack. It was then that Taylor encountered the deadliest member among of the Jiralhanae, the future leader of the Banished, Atriox. Atriox glanced at Taylor and then granted the soldier some time to try to escape from his wrath. Taylor was unable to out run from Atriox far before stumbling down to the ground. Atriox then unleashed his built up anger of his fallen brethren during the war and killed Taylor with his gravity hammer. A recording recovered from Michael Taylor later revealed that a fight immediately broke out between Atriox and another Jiralhanae. This recording was later analyzed by the Spirit of Fire's AI Seth to confirm another early encounter between Atriox and the UNSC during the Covenant War.
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