Once you have found a supplier of this substance, you usually explain what kind of dream you desire (one where you becom Sultan, or a great warrior, or an accomplished artist, along with erotic dreams are the most common themes). In some cases a small blood sample might be required to ensure that the dream is actually focused on some personal element (e.g. a widower who wants to have a dream about his now dead spouse) but most of the time it is not needed.

The substance loses potency in a week or so: if you just want a run of the mill erotic dream you have some chance (9+ on 2D6) to find it ready at the shop; the selller will inform you for how long it can last (1D6 days). More exotic stuff will be available only on 11+ on 2D6. Preparing a new batch requires 1D6 days (but it can also be impossible if you are looking for something exceedily specific).

The process will yield 1-3 doses. A single dose costs like two bottles of the finest liquor. Buyer is expected to pay for the whole batch (i.e. if the yield is 3 doses, user should pay triple price), especially if the dream was customized.

The substance looks like a finely ground bluish powder. It is said that an expert can discern the type of dream based on the hue, but this is might be just a legend.

The powder can be used in two ways: either mixed with water or some other drinkable substance (see below for the taste) or dissolved in oil and incense to be burned in a brazier in the same room where the user will lie to sleep.

In both cases the first effect is equivalent to a mild sleeping drug (i.e. will made the user drowsy and facilitate him or her to sleep, but the effect is not very strong and can easily be countered even just by washing the face, talking a brisk walk, or drinking tea, coffee or similar beverages).

The sleep - if undisturbed - will last 3+1D6 hours. No ill effects have been ever recorded (it would be theoretically possible to create a nightmare inducing version of the drug, but this is discouraged just like dealing in poisons would be for a chemist).

Using the drug is considered safe (no risk of overdosing, no known allergic reactions, addiction seems to be a psychological instead of physiological effect). As soon as the user falls asleep, he or she will experience a generally positive, uplifting, nice dream. Interrupting the dream is possible (the user will be deeply asleep but purely mundane methods will suffice) and the only ill effect is that the awkened person will probably by angry at having been interrupted.

Despite this, many rumors hint at unexpected ill effects and in general is considered something that only decadent sybarites would use (a bit like absynth in Europe in the XIX Century).

The drug is said to be more or less tasteless but tradition requires that it must always be mixed with herbal ingredients giving it a sharply bitter taste (hence the name). According to traditional tales, this was a way to make sure that no children would ever consume it by mistake, and administering this drug to a child is still considered a very serious crime, punishable by slavery (for whoever sells it in the unbittered form) and death (for the person that tricks, allows or forces a child into using it).