On a first glance the World of Mists seems to resemble our own. People live on a (usually spherical) world and gaze at stars in the sky, but there the similarity ends. Magic is a fact of live here. Enspelled lights, enchanted swords, sorcerers throwing fire, lightening and fiends at each other are as much a fact of life as the growing of people and crops. The impact of gods extends beyond the clergy and those attending their services. If a god is displeased, there might quite well be directed lightening bolts, famine or plague, particularly with some of the more ill-tempered deities. They are as real as the magic they give to the faithful.

Crystal Spheres

People have successfully reached for the stars and sail the void between the worlds. The void is not endless here, it is contained within a crystal sphere containing the sun and several worlds. The stars are essentially glued to the inner surface of the sphere, though it is so massively large that once spacefarers can see it, the shell seems like a plane. The exact nature of the stars varies from sphere to sphere. They can be gates to the place of radiance, positive energy, fire, eyes of the gods, windows to the world ocean and many other things.

The World Ocean

The spheres themselves are suspended within the world ocean, consisting of an elusive glittering substance called phlogiston. The impression of the world ocean has been described of an endless kaleidoscope of scintillating bright colours in constant motion. It is known that spelljammers can travel the world ocean suspended within their atmospheric envelope (see "The Spelljamming Backbone"). One should not ever ignite anything in the world ocean, because its highly incendiary substance (known as phlogiston) bleeds through the atmosphere and causes major explosions, while it does not seem to otherwise harm people travelling the ocean. Fire is one of the most dangerous hazards of ship travel.

Within the world ocean, the crystal spheres are arranged in clusters. It is not known why worlds tend to cluster together, but the worlds within a cluster seem to have a unifying theme. The worlds within the Oz'Nihead cluster have recently discovered each other and are at the brink of a new age, within a time of hope and danger. Spheres within the dark cluster are tough and dangerous places, where even survival is often a serious problem and most adventures are about getting whatever is necessary to go on. These worlds are marked by strife and exceedingly dangerous people, who usually mean trouble anywhere else. Fortunately clusters tend to be pretty far away from each other, at the brink of most vessels' air supply.

One last thing travellers should be aware off is the fact that there are streams within the world ocean. Just as there are streams within earthbound seas, they exist within the flow. Going with a stream can massively shorten travel time to another sphere, while going against one is insane, because the journey can take up to ten times longer than it does into the other direction. Travelling without streams is a middle ground, but is rarely done, because there is no other reliable way to navigate within the flow. In addition streams for some reason always lead somewhere. Not necessarily a nice place, but at least one where habitable worlds exist.

Gravity

Gravity is one of the things that do not work as one would expect in the World of Mists. There are two types of gravity, centred and planar. Centred gravity is what most expect, drawing objects to the centre of a larger usually roughly spherical Object like a planet or a large asteroid. Its pull will only be felt on Objects of three miles (sphere) radius or larger to create a noticeable pull for spacefarers. The strength of the pull increases with sizes of the object in a pretty linear way. (Note: In game terms the increases in gravity are measured in steps to keep bookkeeping easier.) Most inhabited worlds have a very similar gravitational pull (and atmosphere, see below). Worlds with lighter or more intense gravity have a tendency to spawn very odd life forms, it will be difficult to even communicate with, even using magic.

Planar gravity is generated by magical Items like an Asteroid Matrix, or a Spelljamming Backbone. As its name implies this type of gravity is a (usually) circular plane that draws everything to it. Knowing how it works allows experienced spacefarers to throw balls around a ship. Anything generating planar gravity also creates an atmospheric envelope (see below). Planar gravity is the standard for spelljammers and asteroid bases, as neither produces enough gravitational pull of its own to properly support living there and maintaining an atmosphere.

Atmosphere

Everything in the World of Mists has an atmosphere, when it is expelled from another one. Most beings take enough air with them to breathe well for two minutes and stale air for another minute, after that the air can no longer be breathed and the atmosphere starts to dissolve slowly. There is no such a thing as decompression in the World Of Mists, because living beings are not compressed carbon and water things, they are semi-mystical beings composed of the four elements and powered by life-force.

Spherical objects having a radius of at least 12,000 kilometres have a breathable atmosphere of their own, as do all objects with planar gravity. An atmosphere is always composed of fresh planar air, unless it is used up or fouled for some reasons. Natural ecosystems like those of naturally inhabited worlds refresh their own air without any aid, while artificial atmospheres usually have to be artificially replenished, either by touching a larger pure atmosphere or opening a gate to the elemental plane of air. Objects of centric gravity tend to bleed their atmospheres away to objects of similar or larger size, while planar atmospheres usually remain intact, only mingling their air with another atmosphere they touch.

Types Of Worlds

Waste Worlds: are desolate and barren of life. Usually they do not have an atmosphere, even though they are large enough to support one. They might have been stripped, abandoned, or simply be composed of elements that do not attract air for some reason. Spacefarers avoid known waste worlds, because they can drain the atmosphere from a ship in some occasions. If they have a residual atmosphere it tends to be exceedingly foul and instantly foul up the atmosphere of any spelljammer.

Gas Giants: are very large worlds as their name implies. When objects are very large, their high gravity does funny things to their atmospheric envelope. The glitter in bright funky colours, which are constant motion. Air constantly forms winds with the force of hurricanes punctuated by twisters and other dangerous atmospheric effects that are rare on other worlds. The winds can tear a spelljammer to pieces within minutes. Sages theorise that beings of crystal or energy could live on these worlds, but no contact has been made so far. If one could construct a vessel able to pass the storms, it would make a very good hiding place, because near the ground conditions (as ascertained by folding golems) are suspiciously calm most of the time. A massive underground shelter from storms might be a good idea however.

Poisoned Worlds: Something went wrong with a poisoned world. Its atmosphere is not just foul, it is plain hostile. Storms, acid rain, brackish oceans and endless barren planes are typical of poisoned worlds. Nothing natural can live here, though it is believed that fiends might have outposts on some of them, but even that is doubtful, because fiends need to be summoned by mortals and cannot stay in our universe for long without aid of their summoners.

Water Worlds: are composed of water for their major part. There might be a few land masses, but generally all live on these worlds tends to be aquatic, or at least amphibian. Usually these worlds have very clean atmospheres, because underwater civilisations tend to produce very little pollution, for the buoyant nature of everything in water and it is replenished well by plants and plant-like beings all over their surface. Water Worlds usually have very calm weather.

Standard Worlds: are inhabited by most spacefaring nations. They offer a good mix of water and land, usually with a tendency of more surface being covered by water. For some reason the gods tend to prefer this type of place for their most complex creations, or for some reasons the nature of these planets supports live very easily. There will usually be a collection of intelligent and less intelligent life forms and plants on these worlds, all interlinked in a complex way and essential to the working of the ecosystem. (Which is usually far less brittle than it seems.)

Artificial Bases: are usually created around asteroids or natural collections of rocks, though a few might have been completely constructed. They all have planar gravity and either various elemental gates or a rudimentary ecosystem so that it can maintain itself, depending on bend of its inhabitants and the size of the base. There is no unifying theme to artificial space bases, but those in remote areas of the void tend to house people who do not like to be disturbed. Rumours have it that there are even artificial bases the size of worlds, but none have been encountered so far.

Other Worlds: can have any type of shape and size. A Cluster world consists of a number of smaller pieces floating within a single atmosphere, still held together by central gravity. Some worlds may be colossal plants, mountains with peaks below and above circled by a disk of water, flat coins flipping through space, rings of rocks, huge buildings from lost races or even only an atmosphere around a well of gravity.