The Fighting Spirit Quest Bug for hunters.

While out in Twilight highlands doing “The fighting spirit” quest. I defeated the “Mullan Gryphon Rider” no less than 4 times without receiving credit for it.

To start the quest the location of the “Mullan Gryphon Rider” which you are to defeat is behind the quest giver… I found it a little confusing as the ones fighting in the area are “friendlies”.
It appears to be a bug only for the “Hunter” class.

The way to solve this is to get the “Mullan Gryphon Rider” health down to about 30% and then dismiss your pet and finish him off yourself.
I hope this helps.