User blog comment:Thornclaw Braveheart/Witch-king of Angmar vs. Eragon Bromsson/@comment-4552610-20111202041342

Because the Fell beast is more maneuverable then the gigantic Saphira, The witch-king could kill Eragon with the Fell Beast without having to kill Saphira. Funny thing how size can be your downfall. And no one can argue that the Fell Beast would be more agile then the a giant but stiffer than hell dragon.