Daedra have a nasty habit of appearing in Tamriel where we least expect them, perhaps the thing for us to do is to always expect them.
I discovered that the Eastern apprentice tower in the besieged city of Elinhir is full of Clannfear. The quarrelsome little beasts are by their very nature aggressive against all but their masters. Swift and nimble, a single Clannfear is more then a handful, but when they hunt together in packs, which they oft do, they can prove to be quite deadly.
Mortal troubles and strife seems to attract them like a Breton noble is attracted to gaudy cloths, but these particular beasts seem to have been deliberately summoned by the Blackcaster Avys Areleth to protect his tower. The High-Elf mage favours the use frost magic, presumably to slow down his adversary giving his daedric pets time to encircle and overwhelm.
The trick to fighting a sorcerer however is to imitate the aggression of the Clannfear. Jump on them quickly, stay on their chests throughout the fight, never let up, and never allow their summoned beasts to come in-between you and your prey.