Here is the list of the possible affiliations and their respective boon; Araqiel (improved defense and endurance), Ezeqiel (thunder magic and calling of storms), Samyaza (necromancy and blood magic), Kokabiel (premonition), Baraqel (illusion magic and mind manipulation), Armaros (nullification of magic), Shamshiel (healing magic), Sariel (improved stealth and sneaking), and Azazel (improved fighting ability, but no magic at all).

The Fallen Angels view those who have made a pact with them as their champions; as you prove your worth om the field of battle, they may grant you greater powers as a reward.

Sadly, right now I am on mobile; I will post a more complete description of each fallen angel as soon as I get on my PC.