Prima Games Myst IV Official Game Guide walks you through Revelation without a hitch. This is the first computer game guide I have ever owned. Usually I mottle through games on my own or seek online cheats. I found having the guide really makes the worlds and puzzles easier to grasp and play.
This guide is a paperback book. It includes the puzzle solutions, concept art, and the back-story. This is a perfect addendum for the Revelation game.
The guide starts you at the beginning of the game and literally holds your hand the entire way. It almost makes the game too easy, if you refer to the guide every step of play.
The Myst series of games are puzzling strategy games. They are supposed to be difficult to test your skills and interpretation. I think using this as a reference when you are stuck is a better strategy--just like using an online cheat, but you do not have to stop or pause play to get help. With the guide, you have help readily available.
The only thing I do not like about it is the images are in black and white. This makes matching scenes somewhat difficult. It is for this fact alone I knocked off a point on my content rating.