Dreamstuff

Dreamstuff is the material which composes the pseudo-physical form of the Dreaming. It is highly malleable by nature, though conscious control of it is elusive.

The forms of fae is composed of dreamstuff, and changes according to their circumstance. Chimera are also made of dreamstuff, though their control over it is extremely limited. Regardless of the appearance of its dreamstuff form, the nature of a fae is apparent (with the sole exception of a disguised Pooka).

• The Dreaming's matter, out of which all forms are constituted, is dreamstuff.
• Ironfell's matter, out of which all forms are consituted, is petrified dreamstuff.
• Virtually every instant of a changeling's life is spent in places where the Dreaming and Ironfell are in conflict.
• The Dreaming (including things of the Dreaming) can interact with Ironfell solely by unpetrifying petrified dreamstuff (generally a long and difficult process, and temporary) — Pooka are again the exception here.
• Ironfell (including things of Ironfell) can interact with the Dreaming solely by petrifying dreamstuff.
• Everything, except Sidhe changelings, has a single form, of dreamstuff (see above). For changelings, who spend all their time in areas of conflict between the Dreaming and Ironfell (see above), this means having a partially petrified dreamstuff form. This means they can interact more or less well with matter of both the Dreaming and Ironfell.
• To be clear, a mortal can only perceive a thing of the Dreaming (such as a changeling's fae mein, which is simply the unpetrified parts of its dreamstuff form) to the extent that that mortal's own form is unpetrified.
• A changeling can be 'obvious' to mortals in a couple of ways: unpetrifying the mortals' forms, or unpetrifying their own form ("Hey, where did he go? He just vanished!").
• Glamour is the name for the changing of dreamstuff (must be unpetrified; see above) forms through the expression/imposition of one's own nature.
• Banality is a measure of how divergent a changeling's mortal soul's (flexible) nature is from the changeling's fae soul's (unchanging) nature. That's brilliant, but I don't know how it works in practice. What causes the mortal nature to veer away from being like the fae nature, given that the fae nature is naturally dominating (or is it?). What is capable of influencing a mortal soul's nature? It would be dull if it turned out that the less dreamstuff you had around you, the more Banality you had, and vice-versa.
• Mortal souls are not glamourous (see above; their natures are not capable of changing dreamstuff).
• Changelings get advantage from their mortal soul's Gift of Liam; they get a certain amount of Glamour directly from themselves. Sidhe get no such advantage, for the human soul associated with the petrified dreamstuff form the Sidhe 'uses' is suppressed.
• Sidhe go to the bother of having mortal 'hosts' because the mortal form of petrified dreamstuff acts as a convenient buffer between their dreamstuff form and Ironfell. That is, while the mortal body is mostly petrified, it isn't entirely, and Ironfell works on that first, allowing the Sidhe's own form to remain pure, dynamic dreamstuff. Why is this good? Well, it's not really (though it would be really easy to spot the Sidhe who was in such bad shape that its own form starting being petrified - leading to having *two* bodies that mortals can see!), though the Sidhe are exactly the sort of people who would be horrified at the thought of any part of their form becoming tainted by Ironfell. The whole set up also means that they don't have Banality, because they don't have another nature interfering with their own. Essentially, then, the Sidhe chose this way because it allows them to continue being pure fae, but exist (as they must) in the no-man's-land where the Dreaming and Ironfell fight it out (see above).