This is the Beasts of Fable Book 1 Legendary Nitun. 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 : Stitched pup, Crystal Spider, and any other undead so he doesnt gain the life.
Set up with DND (plauged blood). Nitun will use a combination of attacks before he uses his prowl. Usualy we would be careful of prowl, but in this case we want the pup dead to ensure 2 rounds of 100% damage buff. Whatever he attacks with doesnt really matter. Were using the Stitched Pup for 2 reasons. 1: He's undead, so when he dies he gets an additional round. And 2, he has howl. When he dies, and your in your additonal round, cast Howl, this will give us 2 rounds of 100% bonus damage. Flip into the Crystal Spider. Use brittle Webbing, and then the swarm. This is known as wowpetbattle.com's classic Spider Burn! If Nitun is somehow still alive.. finish him off with the spider or whatever else you brought with you.