From the introduction:
The Angels of Tangut are not necessarily like the Angels you know and love. Whether they are God's creations and servants even they do not know; they merely follow where they know they must go. Angels normally appear as beautiful women or toned and handsome men (any Angel can appear as either; they have no sex of their own) but they can also appear in Angelic form – four winged and rimmed with a nimbus of light. They are dominated by two aspects: Earth; their ability to perform as mortals, albeit mortals with unnaturally superlative abilities and Sky; their ability to fly and perform great magic. All Angelic magic seems to be a Glamour of sort – an Angel wishing to smite a foe might leap far into the air, snatch the sun from the sky and hurl it at them killing them in a fiery inferno yet when the spell as passed, only their foe would be harmed – the grass around unsinged, even their clothes intact.