Niles' concept of the different realms layered around each other is an interesting one. And his portrayal of the different beings (elves, drwarves, airies, etc.) is also good. However his character development is far to shallow and his imagry poor. He did not exploit the full potential of this story; it could have been much more. In addition, Niles seems to have a fixation on gore and sex which are used inappropriately (in my opinion) in the book. His use of sex in the beginning of the book added no value. His dwelling of the gore of the arcane Delver is as close to deep character development that he gets (which isn't very deep).