Already been done.

Martin has stated that the first thing he wrote about when he put pen to paper was the image of Bran and company in the snow, around the dead direwolf -- which is quite an ominous portent in light of what happens in the series, and a somewhat fantastical one.

He has said that he had considered having _no_ overt fantasy elements whatever, but rejected this -- instead he chose to gradually increase the magic in the series. He wants to keep it rather mysterious, as in Tolkien, although it's clear that it is getting a bit more prevalent. Still, I doubt we'll ever see wizardly duels.