Posted by: Halopedia
The title of Arbiter is the highest possible honor bestowed upon a Covenant Sangheili by the Hierarchs during a time of need, and is also the highest rank in religious significance, although the Councilor is superior in political or military rank. The Arbiter acts as a sort of field general, going on missions for the Prophets and during incidents such as the Taming of the Hunters, the Grunt Rebellion, The war with the Humans, and most recently, the threat of the Heretics.
The Arbiter is sent on the most perilous and suicidal missions in times of when he is needed. On those missions, the Arbiter is expected to die (which they do, in most cases) and become another great martyr of the Covenant on their path to the Great Journey.
Rank of honor.
Posted by: Halopedia
In a Halo Wars cutscene it shows Ripa 'Moramee, the current Arbiter of the game, being pushed off the side of the platform and then the entire area destroyed by a super nova. So, the Covenant would have to have made another armor set to be used for Thel 'Vadam(thus would have been nessecary anyway as Ripa was massive, even for a Sanghieli, while Thel was of average stature). Also, this would mean that his crypt in the Mausoleum of the Arbiter would be empty.
Posted by: Halopedia
Although the prophets say that the Arbiter armor is passed down, this would be impossible as it would often be severely damaged or Irretrievable due to the suicidal nature of the Arbiters task, as well as variation in the wearers stature (such as the enormous Ripa 'Moramee who would need a 'Tailored' set)
New armor is made, but likely using the original specs to keep it traditional.
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