This skill is only available as a part of the Alchemist or Herbal trade. This is a dubious art, at best, and most practitioners of the Herbals’ and Alchemists’ crafts that are pious followers of the Light refuse to even admit they have the knowledge, much less practice the compounding of such substances.
Like many of the other Alchemist substances, the strength of these substances are all measured in Levels of Potence, or just Potence (POT).
While the PC is able to compound to compound substances to affect any specific body systems desired, as discussed in the descriptions of Poisons in general in “The GM’s Toolbox”, it is advised that the player and GM look over not only the various natural poisons described in the Grimoire under “The Substances of Magick” where several are to be found, but also the animal venoms in the Bestiary, where the effects are described in details in regards to game mechanics. A number of mineral/chemical compounds are also available specifically in the Alchemist’s lab, used in a number of processes, which are also poisonous in different ways and to various degrees which will allow the character to manipulate the nature of the poison to achieve the effect he desires. Some may be caustic, inflicting a minor burn to compromise the barrier of the skin and deliver the poison, while others might be compounded of a substance that passes easily through the skin while leaving no trace, except perhaps a bit of tenderness or redness.
The player wishing to engage in this aspect of the craft must get together with the GM, explore the reference resources provided in the GHB I, and discuss what it is specifically the PC wishes to make.
The materials for the making any of the substances described in this skill cost 8d. + (1d. per POT) per dose, however much that may be in STA per volume for the applicable substance.
The Alchemist’s att. mod. for concocting substances poisonous substances is based on his AWA and CRD.