From Halopedia, the Halo wiki
During the Human-Covenant War, Ordo 'Mal served within the Covenant military as a Wraith pilot. His kill count was unrivalled by any other Wraith pilots, being responsible for the deaths of at least 654 UNSC personnel during the course of the war.
After the Great Schism and subsequent collapse of the Covenant empire in late 2552, 'Mal returned to his native keep where he united a network of feudal raid lances under his aggressive and mercenary leadership. After the Sangheili civil war had begun to wane, he was approached directly by Atriox himself for service in the Banished. 'Mal and his mercenary raid lances would join the Banished, becoming known as Kaepra's Grief.
Since the fall of the Covenant, Ordo 'Mal's deathtoll had increased to over 1,200, with many of those earned during the Banished raid on the UEG colony of Palghanar. In recent years, 'Mal found increasing favor with War Chief Escharum, which resulted in him receiving the title of Wraithmaster and in his becoming one of the most dangerous elements in the Banished's combat stratagem.
'Mal participated in the Installation 07 conflict in 2560, during which time he served as part of Hydorskrill Pack in the Eighth Combat Element of Kaepra's Grief. The Weapon would discover the Wraithmaster's location and provide this information to Spartan-II John-117, who hunted down and killed Ordo 'Mal, as well as the forces accompanying him.
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