From Halopedia, the Halo wiki
Early life and Covenant service
En'Geddon was born in Zomar, a major city on the Jiralhanae colony-moon of Teash where much of his clan, the Bulwark of Bone, was located. He would go on to join the Covenant military and serve during the Human-Covenant War.
While still a mere foot soldier, En'Geddon fought during the invasion of the human colony known as Algolis. It was here that he served alongside Atriox and Decimus. When the two Jiralhanae decided to revolt against the Covenant, En'Geddon joined them.
In order to serve Atriox to his full potential, En'Geddon returned to his clan in Zomar, rallying them to join the Banished alongside him. Forging the role of Chieftain for himself, he returned to the Banished as leader of the Bulwark of Bone, now a distinctive subset of warriors within the Banished. It was here that En'Geddon would gain his destructive renown. He would carve a violent path through dozens of human colonies, most notably Seaford and Vuryonos, large-scale raiding operation that left the planets crippled.
These actions caused En'Geddon to come under attention of the UNSC during the Installation 07 conflict in 2560, for which the Chieftain was present. Ultimately, he was identified and located by the Weapon, who passed this information on to Spartan-II John-117. The Spartan proceeded to track down and kill En'Geddon, as well as the forces accompanying him.
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