Spelljammer is a campaign setting for the Dungeons & Dragons role-playing game. It introduces into the D&D lexicon the Ptolemaic concept of crystal spheres (each of which is roughly the size of a solar system), which may contain multiple worlds and are navigable using "spelljamming ships"--magical airships which are operated by the power of magic and are capable of flying into not only the sky but into space. With their own magical fields of gravity and atmosphere, the "ships" involved tend not to resemble the spaceships of science fiction, but galleons, animals, or even more wildly fantastic shapes. Both alien space ("wildspace") and planets are inhabited by strange and dangerous creatures unknown to "groundlings." The alien races engage in spelljamming and space warfare as well.

Travel between different crystal spheres is accomplished by journeying through the phlogiston, a highly-flammable medium in which the spheres are suspended. While the distances between spheres are vast, fast-moving currents in the phlogiston can shorten travel times if properly navigated.

The Spelljammer setting is designed to allow some fantastic space adventures to take place within the traditional sword and sorcery milieu of Dungeons and Dragons; it also provides as a vehicle for crossovers between other D&D settings, in much the same fashion as the Planescape setting. Though the cosmology is derived largely from the Ptolemaic system of astronomy, many of the ideas owe much to the works of Jules Verne and his contemporaries, and to related games and fiction with a steampunk flavor.

Each of TSR's other campaign worlds had their own sections in the Spelljammer Boxed Set - Realmspace for the Forgotten Realms, Krynnspace for Dragonlance, and Greyspace for Greyhawk. Along with the new sphere - Clusterspace - they were known as the "Big Three and Astromundi".

Spelljammer also refers to a specific ship that exists within the campaign setting. The Spelljammer is an huge living ship that appears to be a huge manta ray with a tail curved upwards in a striking position. On its apparent backside are numerous buildings that form a city, inhabited by the common D&D races (Humans, Dwarves, Elves, Halflings, Gnomes, Orcs, etc.) and some less common ones. As a living thing (though this term is debatable since it is unknown what the ship consumes), the Spelljammer has a complex life cycle and means of procreation. Normally the ship has no captain and wanders the cosmos seemingly aimlessly. When the Spelljammer has a captain though, obtained through another complex process, it will create Smalljammers, miniature versions of the Spelljammer, that go forth as its spawn. Apparently there can only be one Spelljammer at any one time. One Smalljammer will mature into a full Spelljammer ship if it is ever destroyed.

For more details on the Spelljammer ship, please consult the Legend of the Spelljammer boxed set, which was released by TSR in 1991.

External links

• Spelljammer for D&D 3e