For all those AD&D fans who were flying through the planes to get the thrill of adventure, this book has simply been a waste. Why is it so popular ? Planescape used to be better and even the Manual of the Planes offered really SPECIFIC rules to go adventuring on the other planes. So why am I upset ? Because this book offers no specific rules ( I mean serious ones) once you leave your beloved Prime material plane. Plane shifting to the Abyss or Pandemonium is as trifle a matter as teleporting to the nearest petty castle. Your magic, your spells, everything is basically left unhindered (well, nearly). All in all, a book for younglings who simply get fascinated at discovering there are brand new planes with sometimes, uh, spooky monsters. For the others, well, a good artwork (hence it doesn't get the insulting one star).