I get it now!
Brackenwood is the island from LOST!!!!! The smoke monster is made up of pixies!! Genius.
Anyway, revelations aside, the movie (as you already know due to the thousands of reviews), is incredible. The animation is perfect, and the artwork is spectacular. You can see how much effort and time went into this by the amazing backgrounds that would have taken days to draw that flash by in an instant. The part where the smoke covers Bitey, and the scenery becomes desolate and bland, was done perfectly. The look of realisation in his eyes, and the last chance he saw when he saw the sky. It was incredibly well done, to give the character such subtle emotions.
P.S. The humour at 6 was for that one moment after Bitey had dashed through the forest, and saw the smoke rise infront of him. The shock, and the "ah, shit" look that followed it was priceless. But again, there was so much animation packed into this that the moment went by in an instant, making it just one more part of why this was so incredible.