Editing Spelljammer (section)

==Fictional setting==
=== Spelljamming helms ===
''Spelljamming helms'' are the central setting concept which allow interplanetary and interstellar space travel for vessels which would otherwise not be spaceworthy, in the form of a [[Ship's wheel|helm]].<ref name="Dragon #154">{{cite journal |last=Rolston |first=Ken |author-link=Ken Rolston |date=February 1990 |title=Role-playing Reviews |journal=[[Dragon (magazine)|Dragon]] |location=[[Lake Geneva, Wisconsin]] |publisher=[[TSR, Inc.|TSR]] |issue=#154 |pages=59–63}}</ref> Any spellcaster may sit on a spelljammer helm to move the ship.<ref name="Dragon #154" /> The mysterious race known as the Arcane is the sole manufacturer and distributor of spelljamming helms.<ref name="Dragon #154" /> Within the ''Dungeons & Dragons'' universe, they are a method of converting magical energy into motive power.

===Gravity and air===
All bodies of a sufficiently large size have [[gravity]]. This gravity usually (but not always) exerts a force equal to the standard gravitational attraction on the surface of an Earth-sized planetary body. Gravity in the ''Spelljammer'' universe is also an exceptionally convenient force, and almost always works such that "down" orients itself in a manner most humanoids would find sensible.

All bodies of any size carry with them an envelope of air whenever they leave the surface of a planet or other stellar object. Unlike real-world astrophysics, this air envelope is not dispersed by the vacuum of space. These bubbles of air provide breathable atmosphere for varying lengths of time, but 3 months is considered "standard".

===Crystal spheres===
{{redirect|Crystal sphere|the fortune-telling object|Crystal ball|Dungeons & Dragons adventure module|Crystal Spheres|the short story by David Brin|The Crystal Spheres}}
A crystal sphere (also known as a crystal shell) is a gigantic spherical shell which contains an entire [[planetary system]]. Each sphere varies in size but typically they are twice the diameter of the orbit of the planet that is farthest from the sun or planet at the center of the sphere (the system's primary).

The surface of the sphere is called the "sphere wall" and separates the void of "wildspace" (within the sphere) from the "phlogiston" (that surrounds and flows outside the sphere). The sphere wall has no gravity and appears to be impossible to damage by any normal or magical means. Openings in the sphere wall called "portals" allow spelljamming ships or wildspace creatures to pass through and enter or exit from a crystal sphere. Portals can spontaneously open and close anywhere on the sphere wall. Magical spells (or magical items that reproduce their effects) can allow a portal to be located. Other magic can open a new portal or collapse an existing one. Ships or creatures passing through a portal when it closes may be cut in two.

Unlike the [[Ptolemaic system]], the crystal spheres are not nested within each other.

===Wildspace===
Wildspace is similar to the outer space of science fiction, with planets, asteroids and stars, but with different physics.<ref name="Dragon #154" /> Gravity is either none or the same as that of Earth, and is directed towards the center of planet-sized bodies; on large objects in space like spacecraft and enormous creatures gravity is directed towards a flat plane running through the object's long axis, allowing characters to stand on the decks of ships.<ref name="Dragon #154" />

===The Phlogiston===
The [[phlogiston]] is essentially a big ocean of a unique element that is neither air, fire, water, or earth.<ref name="Dragon #154" /> The phlogiston (also known as "the Flow") is a bright, extremely combustible gas-like medium that exists between the Crystal Spheres. A signature property of the substance is that it does not exist within the boundaries of a crystal sphere, to the degree that it cannot be brought into a crystal sphere by any known means up to and including the direct will of deities. Every crystal sphere floats in the phlogiston, very slowly bobbing up and down over time. Travel between Crystal Spheres is facilitated by the formation of "Flow rivers" &mdash; sections of the phlogiston which have a [[wikt:current|current]] and greatly reduce travel time. Travel through the "slow flow" (i.e. off the Flow rivers) is possible, but very dangerous.

===The ''Spelljammer''===
The ''Spelljammer'' is a legendary ship which looks like a gigantic [[manta ray]],<ref name="Dragon #154" /> and houses an entire city on its back. All spacefarers (people who live in wildspace) have heard of the ''Spelljammer'' but very few have ever seen it themselves. It is this ship that gives its name to "spelljamming", "spelljamming helms" and anything else connected with spelljamming. The ship has been reported to have been seen in countless spheres for as long as records go back. Even some groundlings (people who live on planets that have very little or no commerce with spelljamming communities) have legends about it. There are hundreds of conflicting legends about this ship, and a mythology has developed about the ship that is similar to the legends surrounding ''[[The Flying Dutchman]]''.

As a living thing (although it does not consume any matter, it does absorb heat and light through its ventral (or under) side and uses them to produce air and food for its inhabitants), 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, 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 its predecessor is ever destroyed.

===Races===
Alien races inhabiting the Spelljammer universe included [[Human (Dungeons & Dragons)|humans]], [[Dwarf (Dungeons & Dragons)|dwarves]], xenophobic [[Beholder (Dungeons & Dragons)|beholders]], rapacious [[neogi]], militant [[Giff (Dungeons & Dragons)|giff]] (humanoid [[Hippopotamus|hippopotami]]), centaurlike dracons, hubristic [[Elf (Dungeons & Dragons)|elf]] armadas, spacefaring orcs called "scro", mysterious [[mercane|arcane]], the [[Thri-kreen]] insectoids, and bumbling tinker [[Gnome (Dungeons & Dragons)|gnomes]]. [[Illithid]]s were another major race, but were presented as more mercantile and less overtly evil than in other D&D settings. The ''Monstrous Compendium'' series added many more minor races. The simian Hadozee were also introduced into the setting, and later incorporated into the 3.5 rules in the supplemental book ''[[Stormwrack]]''.