Archangel
In the absence of God speaking to the Elohim through Metatron, they have to govern themselves through The Host. This council consists of the most powerful and exalted of angels, known as Archangels. These beings are not just powerful versions of their servitors, they have reached a higher level of the Heavens and control enormous power. But this power comes at a price. Their forms are magnificent enough that they can't move through the Thicket of Thorns and must rely on servitors to do their bidding.
Every Archangel is tied to a concept and their power waxes and wanes as their interpretation of that concept gains or loses influence in other worlds. The Foundation and especially humanity, is more powerful in this than anything else. This is why much of their focus is on spreading their influence on Earth. But history has shown that doing so openly leads to undesired consequences and so the angels remain hidden from those not already aware of the worlds outside.
Appointment
The Host has the power when joining forces to elevate an angel to the status of Archangel. Since this is both taxing and gives the new member of their inner circle a lot of power, this isn't done lightly. Only a handful of times has it happened within the past tens of thousands of years.
Duties
Archangels create new angels when needed and they have the power. They also manage those in service of them, both to give the angel purpose and to push the Archangel's agenda. They know that they are the closest thing to a Divine voice as there is, and do their best to take that seriously. Of course, they are single-minded beings with a very specific idea of what is Right and they have no scruples when it comes to enforcing this idea.
Grounds for Removal/Dismissal
It is theoretically possible for The Host to strip an Archangel of their position. There are a few cases where this is rumoured to have taken place, but the Host is remarkably quiet on the topic.
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