Board Thread:Questions and Answers/@comment-1031724-20160618003023/@comment-28547359-20160619070827

Qyburn is a Maester who has some knowledge of magic. In the books and in the TV show, it's shown that magic was/is involved in the making of the white walkers. The white walkers were created to be mindless fighters for The Children. I wonder if Qyburn figured out how to crudely recreate that process for Gregor's body.