From the publisher:Go beyond the fields we know, into the realms of high fantasy and legend. The planes are a far grander stage for adventure than the mundane wilderness and dungeons of the world. Out there, the characters can walk with the gods themselves, delve into the foundations of the cosmos or quest in the lands of the dead, and be the deciding factor in the great wars of Good and Evil. This is truly a place for heroes.The Book of the Planes describes the myriad planes of existence in further detail, offering encounters, hazards and adventures in dozens of worlds. Beginning with the elemental planes of Earth, Air, Fire and Water, we travel outwards through the transitive planes of the Ethereal, the Shadow Plane and the Dream plane to the wild Energy Planes of Positive and Negative Energy. Beyond them, we come to the wide gulf of the Astral which leads to the Outer Planes. - BoardGameGeek