Apparently, there is an
alchemy month going on. That's neat, since I've been thinking a lot about alchemy now that my campaign is on pause. Here are my rules. They are not at all playtested, but at least in theory I'm really happy with them.
The basic idea is that alchemy should be about formulas, trial and error. The system therefore makes a strong distinction between simple player-facing rules which are basically "say a prayer, and follow the formula" and more involved referee-facing rules which governs how formulas should be designed. For most players, alchemy is consequently about finding a formula and questing to retrieve the ingredients. For those who want, however, alchemy instead is about trying to understand what makes the potion effective, and/or trying to improve it.
Hopefully, you can find some ideas worth stealing. An example formula can be
found here; and there is plenty of inspiration for more over at
Slugs and Silver.
A system for Alchemy
PLAYER-FACING RULES
Alchemy is a craft based on a secret system of mystical correspondence. To create an alchemical potion, your character needs
- A formula
- The required ingredients
- Paraphernalia and tools
Any character possessing these things can be an alchemist. To become a master requires understanding the correspondences that govern all of creation - a task that may easily consume a lifetime.
Preparing a potion
Before preparing a potion, alchemists commonly fast, say a prayer or invocation that will compensate for their impending blasphemy. Failure to take proper precautions results in minor corruption (-1 Spirit).
After these precautions, just follow the formula.
Determining the Effect of a Potion
The potion's effect is determined by three things
- The formula
- The alchemist's INT
- How closely the formula was followed
When the potion is used, or otherwise tested, roll d20 and add INT of the character preparing the potion to determine its quality.
Formula was followed exactly
- the potion always has effect
- failed INT-roll means side effect: minor corruption (-1 Spirit)
- natural 1 means side effect: major corruption (-1d4 Spirit)
- natural 20 means potion not depleted; it was so effective it can be used again
Minor deviation from the formula- the potion only has effect on successful INT-roll
Major deviation means the potion never has effect.
Creating new formulas
If a process involving minor deviations is successful, it can be codified into a new formula. Once codified, it is no longer considered a minor deviation for rules purposes. To codify the process, the player simply writes it down.
Prepared potions
A prepared alchemical potion should be noted as
"Potion of healing (minor, +3)"
indicating the formula used, how closely the formula was followed, and the INT of the alchemist.
REFEREE FACING RULES BELOW
REFEREE FACING RULES
For referees only, below image.
The Formulas
There are three basic types of alchemical formula:
- Pure
- Diluted
- True
When designing formulas, you start with the Pure.
The Alchemical Principles
To design the formula, you first decide what class of potion it will result in.
There are four alchemical Principles, or classes of potions, corresponding to a colour each. All potions use a base that is determined by their principle. They are
- White (purify, heal): White wine, distilled alcohol, fermented milk, or other white/clear liquid intoxicant
- Yellow (enhance): Ale, Mead, or other yellow/golden liquid intoxicant
- Red (alter): Red wine, or other red liquid intoxicant
- Black (?): Ichor
A healing potion will thus be white, a potion of giant strength yellow, and a potion of growth red. The black are there as a possibility; not currently part of my campaign.
The Pure formula
The Pure formula consists of 5 components
1 base- An intoxicating liquid of a colour determined by the Principle of the potion.
3 ingredients
- A natural ingredient (something from nature)
- An unnatural ingredient (something made)
- A preternatural ingredient (something with magical or mystical properties)
1 reagent- Salt or potash gives a normal potion
- Sulphur gives a weak potion (+3 to INT roll)
- Mercury gives a strong potion (-3 to INT roll)
Diluted formulas
Over time, many formulas become diluted when passed from Alchemist to Alchemist, or developed from flawed understanding of the pure process. A diluted formula has the same effect as a Pure formula, but contains more than the 5 required ingredients. These additional ingredients may give side effects, but are commonly just cosmetic. For example: an alchemist may decide to add honey to a potion where honey is not required, just because they prefer the taste or to see if a rival alchemist is stealing their formula (and thus also including the unnecessary honey).
Using a diluted formula means characters have to collect more ingredients, but otherwise carries no penalties.
True formulas
Through clever substitution (see below), it may theoretically be possible to create a formula with less than 5 components. The hypothetical formula using the least number of components to create an effect are known among alchemists as True formulas.
Substitution
Alchemy works through correspondence. Thus, all components can be substituted with another component of sufficent similarity. For example, red wine may be substituted as a base by blood and white wine, and a hippogrif egg might perhaps be substituted by the egg of an eagle raised among horses. Substitutions like these are considered a minor deviation.
If a substitution is successful (meaning: the character succeeds with the INT roll to determine the potion's effect), the character can codify the process as a new formula. In game, this is done by a player writing down the process. Through iterative attempts of substitution and codified processes, a clever alchemist might eventually arrive at a formula that is very different from the original.
