Ok, so I lied. I am going to discuss something else before the moons of Theyra. Sorry. My wiki, I can do what I want. Next time, next time we will discuss the moons.
The Crystal Sphere of the Theyra System
Following the epicness that is Spelljammer and adding some of my own twists to it, I decided to explain a little bit about how Theyra and the planetary system that Theyra is a part of works. This is somewhat important for a couple of the moons of Theyra, because of the lack of atmospheres of said moons (I will get into more detail when we discuss the moons).
Just like in Spelljammer, the Theyra System is surrounded by a huge crystal sphere. The whole system then floats in an ocean of what is called the phlogiston. Beyond the phlogiston is wildspace. Both phlogiston and wildspace function mostly like they do in Spelljammer, except wildspace is much more science fiction space-like than the fantasy version that Spelljammer introduced. Once a vessel moves beyond the phlogiston, the vessel can run into trouble unless it is built for true space travel.
Within the crystal sphere, things are very different. While officially on the Prime Material plane, the space between the various planets, planetoids, and other celestial bodies, is incredibly unique. Instead of cold, nearly dead void, the space is made up of the Astral Plane that has over the eons seeped into the Prime and become trapped in the sphere. Planets that have atmospheres naturally keep out the astral energies. Because it is not as concentrated as the Astral Plane, most of the traits of the original plane are diluted. Over the eons the astral energies has become known as the Astral Shallows or the Astral Sea.
Astral Sea/Astral Shallows
Gravity: Subjective, Special. Any large item of enough size will generate gravity. The individual will be drawn to the biggest item.
Shape and size: Finite
Morphic trait: Divinely Morphic
Elemental/energy traits: None
Alignment traits: None
Magic traits: Limited – Enhanced (All)
Faith traits: None
The Astral Sea, because of its magical nature, has a breathable environment to any creature that enters it. The magical nature also creates a temperature that is survivable, if a bit cold, for any living creature that enters the sea. This can vary depending on the creature and even two creatures that need different temperatures standing next to each other will be comfortable.
Movement among the Astral Sea can be done in a couple of different ways. An individual or object will stay stationary until they are moved by something that strikes them. Just like real physics, the individual will then be moved away from the moving object. Additionally, an individual or object will be drawn toward anything with a larger and more powerful gravity field, such as most planets, asteroids, stars, and anything else that can create its own gravity field.
Entities with intelligence or wisdom of at least animal level discover they can move through the Astral Sea at 5 feet x the average of their intelligence and wisdom score. For each + 1 modifier of intelligence or wisdom that an entity has, the entity can add its normal movement to its base movement. For example, a human with a base movement of 65 feet and a + 1 modifier to intelligence, can move a total of 95 feet in one round. This movement feels almost like swimming through water. A strong gravitation field will overcome this movement and draw an entity towards the item that is creating the gravity.
The last form of movement is through the use of both astral and cosmic winds. Special sails can be built that can capture the magical and psionic winds that blow through the Astral Sea. Additionally, solar sails can be built to capture cosmic winds and use them to drift across the sea.
The Astral Sea, because of its relative hospitality to live, does have a form of ecosystem that has formed. One of the most interesting are the pods of psychic Astral Whales that make their way throughout the crystal sphere, feeding on plankton and absorbing energies from the Astral Sea. Coming from a branch of Blue Whales that somehow found their way to space; the Astral Whales are now more intelligent and capable of various psionic feats, such as telepathy and mind reading. These whales also seem to know where the portals to the true Astral Plane within the Shallows hide and use them to go back and forth as needed.
Other critters, monsters, and animals also hide throughout the crystal sphere and the Astral Sea. These can act as encounters for adventurers who are exploring the Shallows.
From planet side, the Astral Sea helps to increase distance starlight, making the night glow and twinkle. The Crystal Sphere does not block any of the distant light either, but it does have a tendency to twist the light causing some shifting of the light source.
The Crystal Sphere of Theyra still has what you would assume from for any solar system, such as asteroids, comets, moons, planets, and other strange space “stuff”.