Cassisian

Cassisians may be the weakest angels, but their faith is strong and their perfect memory ability can make them precious eyewitnesses.

When donned, a helm in a treasure hoard unfurls its wings and reveals itself to be a cassisian.  Its memory and protective aura are useful, but its constant sermonizing about the need to fight hobgoblins may alienate reluctant wearers…or drive eager disciples to rash acts of bravado.

A newly manifested cassisian’s form is that of a helmet of a recently fallen general.  Assuming the angel and the general are one and the same, the cassisian’s spirit might know the battle plans that could save a nation—if it can be induced to remember its former life (if any).

The stereotype of the agnostic, deity-defying wizard is often overdone.  Good-aligned wizards in Corym are quite mindful in their devotions, and summon cassisians to serve as their familiars, advisors, and confessors.

—Pathfinder Bestiary 2 26