This is the Beasts of Fable Book 3 Legendary No-no. The quest can be picked up from Gentle Sans, located in the Shrine of the Two Moons at 60,23. For this Encounter were going to use : I prefer three s/s Ravens, but it can vary. Any crow/raven combination will work.
We have the speed advantage here, so lets get to work. Start by dropping darkness. This is going to do some damage and set him up for nocturnal strike. he will return fire with tail slap. Normaly he will cycle Tail slap, Beaver Damm and Dive. The great thing about his dam is that it absorbs TWO attacks, including HIS! So just let him tear up his own dam by passing the rounds when its up. This fight is just keeping Darkness and Nocturnal strike on CD, and spamming alpha strike. Keepin gin mind to allow his own dam to mitigate his damage.