User blog comment:FTWinchester/Season 9 concepts/@comment-86.132.20.55-20140117234057

Angels who might be on Metatron's hit list because lets face it he has to be killing the other angels for a reason.

Kasbeel: The oath and secret keeper. Kasbeel is a living recorder and holds all of heaven's greatest secrets inside him making him very valuable to both heaven and hell, especially since he may hold the secret to breaking Metatron's spell. To keep the secrets safe he was rendered mute so he would not reveal the knowledge either willingly or under toture but that's a risk Metatron will not take.

Kushiel: The punisher of the dammed. He is a unique angel who walks in both Heaven and Hell and punishes those who have sinned in the most severe manner. He is essentially one being split in two with one half existing in one place and the other in Hell. This makes him somewhat immune to the spell since it only banished whole angels so his heaven essence remained "upstairs" meaning he could spy on Metatron. He would have to be killed by finding a relic to summon both halves to earth to be killed at the same time,