Perfection.
There are 5 bosses on this game, all of which are more than a simple kill to proceed character, but have their own stories to them. I loved the direction that this was taken, simply because I have never seen anything like it before. Excellent job on the small details as well, I enjoyed lighting the continent on fire as I flew to the next boss. The final boss, the huge dragon of doom, was the perfect final face-off, with just the right amount of challenge built in to keep it interesting. Also, to others out there, some parts of this game take awhile to progress, so if it seems like you have been in the plains on a loop for 5 minutes, wait 5 more :P You will find that everything progresses eventually.