It seems that the effectiveness of poisons, both in the core list as well as in homebrew systems for inventing your own, are balanced with and directly proportional to their cost. However, there are many poisons that are craftable in real-life at trivial cost.
One of the greatest examples is the semi-infamous Potato Tea. Potatoes are a form of nightshade, a grouping of plants known for their poisonous qualities, and sure enough, almost all parts of the potato plant are poisonous (including the part we eat if not boiled and much more so prior to modern genetic modification, and most concentrated in the leaves). Boiling a potato and/or it's leaves causes the poisons to seep into the water, and instantly creates a poison that is deadly when ingested.
This example seems to create a logic-bomb when applied to the balancing of poisons. The cost of materials is about 1 to 3 cp, and the crafting difficulty as routine as the ability to boil water. Notably, this is only one example of countless ways to make cheap and easy poison using real-world logic.
There seem to be a number of ways to handle this inconsistency:
- Do not allow it at all, banning the very concept.
- Make the poison weaker proportional to its gold value regardless of realworld properties.
- Make the poison cost more proportional to its strength regardless of realworld properties.
- Allow it and ignore the poison rules and their inconsistencies altogether.
What is the way to deal with this strictly by the rules, and is it truly in conflict with real-world logic? What is the most common or reasonable way to deal with this situation if it is considered in conflict with the rules? Are there houserules, homebrews, or a general consensus on the subject? Has anyone tackled this rules inconsistency before?