Reindeer

Reindeers were intelligent, fast, and excellent talking beasts that were only mentioned in The Lion, the Witch, and the Wardrobe where they are pulling the White Witch's sled and Father Christmas's sled. The ones that carried the White Witch's sled were called White Reindeer that were followers to the White Witch. Brown Reindeers were on the side of good where they carry Father Christmas's sled.

Reindeer in the Chronicles of Narnia Books
Reindeer were mentioned in the second Chronicles of Narnia book, The Lion, the Witch, and the Wardrobe. The reindeer came in two known coat colours, white and brown. The brown reindeer were larger than the white reindeer. Reindeer pulled the sleighs of Father Christmas and the White Witch. The White Witch used white reindeer to pull her sleigh, while Father Christmas used brown reindeer. The reindeer in the book appeared to not be able to talk, although it was never mentioned one way or another. If the reindeer were, in fact, non-talking beasts, then they would have been neutral, rather than taking the side of Aslan or the White Witch.