The Choking Cloud
Dust / the Wasting Place
Users of the spell airy dust be warned! The region of Dust known as Choking Cloud, kills many travellers dead. Observable only as a thinning of the Dust and a lightening of its colour, the Choking Cloud is made of fragments of dust that are poisonous to almost all non-elemental life forms.
Basically, if a basher has blood or ichor, and eats or breathes this dust (even as an airy dust spell), he must make a save versus poison or die instantly in considerable discomfort. A successful save indicates 2d20 points of damage (no further saves are required until the area is left and re-entered).
There’s a thriving black market in this stuff (so called because the victim gasps for breath before the skin turns blue and death occurs) as enterprising (and foolhardy) cutters travel to Choking Dust to gather the poison. It’s especially popular with assassins because (apparently) it tastes like salt, and is therefore almost certain not to be detected in food until it’s too late. Despite being strictly illegal in most civilised places, it’s not that hard to get hold of.
However, it has come to the attention of quasielemental spirits of Dust that more and more of their precious plane is being stolen, and a group of them have decided to take matters into their own dusty fingers. Thieves using no breath spells or similar magic to protect themselves have been hit by dispel magics, physical attacks from angry dust denizens, and barricades on the better known portals near the region.
Source: Jon Winter-Holt