Councilors held a very high position in Sangheili society. They acted as members of the Covenant High Council, along with the Lesser Prophets. Their power is derived directly from the High Council, under only the Hierarchs, making them some of the most important roles held in all of Covenant society. Councilors are known to carry Energy Swords, which indicates their status within Sangheili nobility, either having been born into it or earned through martial prowess. Due to the compulsory status of military service among Sangheili in the Covenant, Councilors would also have been retired veterans.
In November 2552 many Sangheili High Councilors congregated near the Control Room for Installation 05, where they planned to witness the activation of the ring at a close proximity. In truth, this was a ruse to separate them from Sangheili soldiers, and were quickly set upon by Jiralhanae units. There were several survivors of this ambush, however, who incarcerated along with Covenant soldiers opposed to the Jiralhanae coup.
As an independent Sangheili state blossomed after the Great Schism, surviving councilors held influence over the new political structure, and the support of some or Jul 'Mdama and other groups against Thel 'Vadam held considerable sway.
Because warfare is the primary purpose of Sangheili participation in the Covenant, Sangheili High Councilors are extremely skilled warriors in almost all forms of armed and hand-to-hand combat. Sangheili High Councilors typically carry the Energy Sword, which also serves as a symbol of their status as aristocrats. Only high ranking officers such as Ultras, and the Zealot corps use such weapons, and the councilors may have served in these ranks. They are also, albeit infrequently, armed with Plasma Rifles, with their accuracy unmatched. Like an Ultra, they will let loose a war cry and switch to their Energy Sword if an enemy gets too close to them.
In addition to their great skill in combat, Sangheili High Councilors are also equipped with an extremely durable Combat Harness, similar in appearance to the standard issue version, but with superior armor compared to that worn by lesser ranks. Additionally, the built-in energy shielding system is capable of taking an enormous amount of damage, equivalent to that of a Sangheili Ultra: they can withstand up to three Shotgun blasts in close range, devastating melee attacks from behind, a hit from the Fist of Rukt, multiple Plasma Grenades or Fragmentation Grenades and even surviving a blast from a Rocket Launcher and a slash from an Energy Sword, even when their shield is down. Halo 2 is the only game in which you see and work with Sangheili High Councilors.
Sangheili High Councilors are easily recognizable by their large, distinct and oddly shaped, ornate headdresses, fixed to a traditional Sangheili Helmet. Their armor, normally the standard Combat Harness adorned by most other regular service Sangheili (with the exception of the helmet), are a pearlescent white, or metallic-silver color, very similar to that worn by Ultra Sangheili, the only difference being that they have no steel markings on their armor as many other Sangheili ranks do. Sangheili High Councilors sometimes wear a different helmet that has the same basic shape, but has different designs and is more open.
- The headdresses worn by Sangheili Sangheili High Councilors closely resemble the Xenomorph Queen's head, from the movie "Aliens"; though it is smaller and narrower. In addition, both Halo's Covenant Empire and Aliens' titular species have caste systems.
Halo 2: Anniversary
- Halo: The Flood (First appearance)
- Halo Wars: Genesis
- Halo 2
- Halo: Ghosts of Onyx