Okay, so my son is asking about a hardcover book I used to read to him years ago (1995-ish). It was a children's dark fantasy illustrated book ala Wind and the Willows, Dark Crystal, Lord of the Rings, with dwarf people and creatures with pale faces, an evil tree and an evil wizard. The illustrations were very good and detailed and reminded him of Jim Henson's characters. He believes the word Gray was in the title, but not sure. And at the end of the story, the main characters sidekick falls off a cliff.