One thing I do remember about that collection was that all the covers were odd looking. They have what I now think of as a tarot card-like quality about them. The strangest one of all was The Magician's Nephew, which shows two children falling upwards out of a pool of water, while a large woman hangs onto them by the girl's hair. The children look frightened, but it's hard to tell if they are more afraid of the woman or of the horrifying fate they will meet if they continue to fall into the sky.
Combine that with the strangely quiet animated version of The Lion, the Witch, and the Wardrobe, which also has sort of a tarot card look about it. As a result of these, I often felt that the Narnia series contained strange mysteries that were better left unlearned. Upon opening one of these novels, you might learn that at the center of your spread is the Children Who Fall Up card, which means you will find yourself having to choose between two equally awful things, both of which may hurt a lot. In the position of who you are, you may find the Lion's Breath card, which means that you are currently unwilling to make changes and are suffering as a result.
Honestly, makes you wonder why these books always get a free pass when the more extreme Christians decide to condemn the inherent evil of the fantasy genre!