Tartarus
Tartarus was the last known Chieftain of the Jiralhanae to serve in theCovenant. He is the Arbiter's primary rival in Halo 2 and acts as theHierarchs' chief enforcer or, more accurately, Truth's second-in-command. He is also the tertiary antagonist and final boss in Halo 2.
Tartarus is easily recognized by his silver fur, very deep voice, his distinctive "Mohawk", and the fact that he wielded theFist of Rukt. His devotion and faithfulness to the Covenant and the Prophets is unwavering, and he strongly represents the general attitude of his entire race: rough, arrogant, and disdainful of the Sangheili. He was a powerful, aggressive, and intelligent leader who inspired both fear and respect in his Jiralhanae forces.
Prophet of Truth
The High Prophet of Truth, born Ord Casto, and formerly known as the Minister of Fortitude, was the leader of the three Prophet Hierarchs that led the Covenant High Council during the Ninth Age of Reclamation, the central antagonist in Halo 2 and 3, and one of the main instigators of the war against humanity. In 2552, he plotted the ousting of the Sangheili from the Covenant, and replaced them with the Jiralhanae after the death of the High Prophet of Regret on Installation 05. After the demise of the High Prophet of Mercy on High Charity, he became the de facto leader of the Covenant, from which position he lead their forces to the Artifact in Africa, and eventually to the Arkin an attempt to activate the Halo Array, where he was later killed by Thel 'Vadam.
Prophet of Regret
The High Prophet of Regret, born Lod Mron and previously known as the Vice Minister of Tranquility, was the youngest of the three High Prophets that lead the Covenant High Council during the Human-Covenant war.
Rash, ambitious, immature, and naive compared to the other Prophets, Regret originally served as Vice Minister of Tranquility, where he worked frequently withSangheili and had adopted some of their personal traits, such as a preoccupation with honor and personal arms. However, he also exhibited traits of alcoholism and smoking. Still, Regret was intelligent and fiercely opposed to Humanity throughout the course of the Great War and expected his soldiers to obey him without question.
Prophet of Mercy
Mercy can be seen as passionate, wise, and knowledgeable, as seen in the cutscene before the level Sacred Icon where he shows his excitement about Halo, expressing hope that the Great Journey should begin very soon. It's very possible that he has a sense of propriety, seeing that he talked Truth out of condemning Regret, as described on the level Regret, but that doesn't necessarily mean that he is merciful. He is perceptible and an authority on the Forerunners and their knowledge, he can be considered the Prophet of Truth's right-hand. Without Mercy to advise him later, Truth becomes much more irrational and aggressive in Halo 3, even toward his subordinates (very much like Regret was before the Great Schism), although it is just as likely that Truth is showing his true personality after years of cool political veiling.
Sesa 'Refumee
Sesa 'Refumee was the leader of the Heretics, referred to in Halo 2 as simply theHeretic Leader, who had taken control of the Gas Mine on Threshold and a smallbase on Basis, the gas giant's moon which Installation 04 rests between.
Ripa 'Moramee was a Sangheili Commander of the Covenant Army during theHarvest Campaign and other Outer Colony campaigns until his demise in 2531. After being punished for leading a coup against his clan leadership and failing onDecided Heart, he was given the rank of Arbiter by the Hierarchs, mainly at the urging of the Prophet of Regret.
In his new role, he led the Covenant attack on Harvest and the excavations of aForerunner artifact on the planet's surface. Shortly afterward, he assisted the Prophet of Regret in an attempt to reactivate a dormant Forerunner fleet on Shield 0459, for which purpose he kidnapped the human scientist Ellen Anders on Arcadia. This led to a series of violent engagements against forces led by Captain Cutter of the UNSC Spirit of Fire, and the eventual death of 'Moramee at the hands ofSergeant Forge during the Covenant assault on SPARTAN Red Team, who were attempting to destroy the artificial planet with the Spirit of Fire's removed FTL Reactor.
Ripa 'Moramee
Jul 'Mdama
Jul 'Mdama (formerly 'Mdamaee before the the Great Schism) was a Sangheiliand the Lord of Bekan Keep in the rural state of 'Mdama, where he lived with his wife, Raia 'Mdama, and his children, two of which are Dural and Asum. He later became the leader of the Covenant Remnant, assuming the title of "the Didact's Hand."