Shtaiur: The Plane of Shadows (Silver Pariahs Supplement)
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It would be nothing short of horrendously impossible for a mortal body to survive even a single round in Shtaiur, much less the ability to observe it. Any of those still among the living who wish to observe this plane would be wise to use Astral Projection and a spell that allows them to see in the x-ray or gamma wavelengths, or at the least ultraviolet. It is also unwise for any disembodied travellers to the plane to wander too close to any of the inhabitants, for though they are not prone to violent actions, they have very strong gravitational pulls and have been known to usurp souls into their bodies, making them a part of their collective. Thusfar, no known cases of one soul noticeably altering a Shtaiurkol have been documented, though when exactly this might'll have had happenen and when'r it may'd haven transpire'll is a completely different matter. The preceding text is not in error, as time flows erratically, and at times backwards in Shtaiur compared to the flow of time on the Prime Material.
This phenomenon is so prominent, in fact, that of the most well-documented traveller to Shtaiur, Seer Vur'Qai had this to say about his travels: "In my first journey, from my vantage point high on the horizon, the locals gave me telepathic greetings from below as though I were an old friend. On my next visit, I incredulously introduced myself as if to complete strangers - though at the least I was granted the courtesy of knowing some of their names, or at least the names by which they are now known. On my third visit, the names were changed, though all the faces seemed the same. Only on the fourth visit was I recognized by any of them, and only about half were faces I'd seen. Truly t'were a mad soul that could've conceived this chaos and thought it just."
There doesn't seem to be a fixed caste system for the Shtaiurkol. They all seem to do whatever task needs doing at the time, in whatever fashion they deem most appropriate collectively. They communicate via telepathy, the range of which being either prodigious in scale, or limiteless within the confines of their realm. Either that, or distance is not quite what it seems to be, though there is always solid (or apparently solid) ground beneath one's feet. Flight, if it can be performed in Shtaiur, has not been attempted, and nothing naturally-occuring in the realm itself has been seen to fly, or even hover. It is a very attached place, and one in which a traveller can easily become inexorably anchored if they wander too close to the central point.
DMs are warned that any venture to this realm, even in dreams, is not recommended until at least 9th level, and phyiscal journeys are never recommended. Escape from Shtaiur after death is not a process that will be barred by the inhabitants, though it is inhibited by the laws of physics, to the point where even powerful magics cannot aid greatly those seeking to return to the land of the living.
One thing is known, however, about the Shtaiurkol. They were once people; the implied meaning of that statement being that each individual Shtaiurkol was once several people who, at one point or another, ceased being quite-so-separate. The greatest collection of not-so-separates in the plane, the de facto leader of the entire race, is Palos Anu-Dur; a name that means "He Who Speaks To You" in an older variation of the Jherron tongue. The meaning, however, is irrelevant as Palos will often speak at great length. Half of the time he will speak to the players of important things yet to come, two thirds of the time he will bore them to tears with history, a quarter of the time he's bound to give them useful insight to their current predicament, and the other half of the time he'll say nothing and yet everything. THe preceding text is presented in a fashion that borders on the level of Douglas Adams absurdity in the context that the DM cannot rationally decide what and wherefor Palos speaks to the players, if he deigns to do so. Time does not work fluidly, and the inhabitants of Shtaiur do not expect anyone that knows them to know them in return, nor for very long.