OK, no more preamble. Here's what I have so far. None of this is written in stone of course -- tear it apart, please. I wish I had a tree-like visualization for you, but not yet.
Alchemy is the study of, extraction, and manipulation of energy from both ordinary and magical materials. It is considered a branch of magic, although it is not concerned with manipulating energy in the same way spells do. In real life, the term "alchemy" is also used to refer to hermetic, mystical, and occult practics which were considered related to what we would now recognize as proto-chemistry; however I will be treating such practices in a separate skill specialty. Here I focus only on the chemistry and pseudo-chemistry type of alchemy.
Unless otherwise stated, a period of "lab work" means that for the given duration, the character must spend a certain amount of time in the lab or there will be a chance of the progress so far being lost. The default assumption is five 4-hour workdays required per week of the duration, and that each missed day means a cumulative 2% chance of all progress and materials being ruined. Finally, the vessels and glassware used in alchemy must regularly be coated with a substance called "fat lute," a mixture of clay and oil which forms airtight seals and protects against fire damage. Each day in the lab is assumed to use up 1d3 oz of fat lute, because once applied, fat lute loses its moisture and becomes useless over time. Surplus fat lute can be stored in an airtight container until it is needed.
The character is ignorant of all alchemical processes, theories, techniques, and products.
Construct Lab (10)
The character possesses the knowledge to safely set up, use, and maintain/repair alchemical equipment. Most alchemy skills require a lab; without this knowledge, the character will only be able to perform those skills if they have gained access to another alchemist's lab.
A character with this knowledge can extract a foam of animalcules by dissecting a creature's genitals. The genitals must be not less than a day old. 1 oz of foam can be harvested from a creature of 250 lbs or less, plus an additional ounce for every further 250 lbs. These animalcules contain potential energy within them which can serve as the base ingredient for certain alchemical items, such as potions. If consumed as-is, 4 oz of foam will restore 1 hit point.
The process of dissection and preparation will take 1 hour per oz of foam, and for each oz of foam an Intelligence check is required for successful preparation. Foam will retain its potency as long as it is kept in an airtight container; it will become useless after an hour of exposure.
Aqua Fortis (10)
The character can produce aqua fortis (nitric acid). This requires 2 days of lab work. Producing 1 vial requires 2 pounds of copper ore (only some of which is assumed to be copper nitrate, the mineral required.)
Aqua fortis can dissolve base metals. It does not react with gold, platinum, or other noble metals; thus it can be used to test the purity of a gold alloy, by seeing how much the alloy's color changes in the presence of aqua fortis.
If used as a splash weapon, a direct hit with aqua fortis deals 3d6 damage.
Green Vitriol (10)
The character can produce green vitriol, also called copperas (iron II sulfate). This requires 1 day of lab work. Producing 1 vial requires 2 pounds of iron ore.
Apart from its alchemical uses in producing certain powerful acids, green vitriol is used in several industries to produce green or blue coloration. It can also be used to precipitate gold which has been dissolved in aqua regia.
Oil of Brick (10)
The character can produce oil of brick with 1 day of lab work. The ingredients are simple: 1 vial is produced from 1 brick and 1 pint of any cooking oil, such as olive oil.
Oil of brick is a medicine. Consuming half a vial will prevent a character from suffering the ill effects of motion sickness, migraines, or seizures for the rest of the day.
Homunculus (20) (requires Animalcules)
By carefully nurturing 12 ounces of animalcule foam, the character is able to cause it to coalesce and grow into a homunculus. The process of transforming animalcule foam to homunculus requires 3 months of lab work.
A homunculus is a lumpy, humanish figure, 18 inches tall. Its body is somewhat pliable and it will both mold itself to complete tasks, and allow itself to be molded. It has 1 Hit Die, which is worth 2 HP per level of its creator; it cannot feel pain, but will collapse into foam if these HP are depleted. A homunculus does not really have any intelligence of its own, but it is able to feed off its creator's mental energy, and respond to its master's commands. It has 3 AP and a Strength of 3 but is totally incapable of making meaningful attacks.
Spirits of Salt (20)
The character can produce spirits of salt (hydrochloric acid). Producing 1 vial takes 2 lab days, and requires 1 pound of salt and 1 vial of green vitriol.
If a vial is thrown, spirits of salt will mist out to a 5-foot radius. All creatures caught in the mist will take 3d8 damage (Poison save for half).
Oil of Vitriol (20)
The character can spend 2 days in the lab to produce 1 vial oil of vitriol (sulfuric acid). The ingredients are two vials of green vitriol.
Oil of vitriol is extremely corrosive. If thrown as a splash weapon, a direct hit deals 3d6 damage; if the splash-weapon save vs Blast fails, oil of vitriol will deal a further 2d6 damage the following round.
Aqua Regia (20)
The character can produce aqua regia, a mixture of aqua fortis and spirits of salt. Producing 1 vial requires 2 lab days. The ingredients for each vial are 1 vial aqua fortis and 3 vials spirits of salt.
Aqua regia is so called because it can dissolve the "noble" metals, including gold and and platinum.
If used as a splash weapon, aqua regia acts as aqua fortis.
Diana's Tree (30)
The character can produce Diana's Tree, a crystallized silver form which embodies alchemical properties of life. The required ingredients are 1 oz of silver, 2 oz of mercury, one vial of aqua fortis, and 20 oz of distilled water. The ingredients are mixed and then left alone for 40 days, at which point the process is complete.
Diana's Tree functions as a strong restorative. The recipient crushes the Tree and rubs the mush on their skin; healing begins the following round, restoring 6 HP per round for one minute, for a total of 30 HP.
Alternatively, as a manifestation of the life force of minerals, Diana's Tree can also be used for the construction of golems.
Brew Potion (30)
The character can create potions. For base ingredients, all potions require 4 oz of animalcule foam and 1 oz of thaumic powder. If the potion has the same effect as a particular spell, the alchemist will need to be able to cast that spell in order to create the potion, but no other ingredients are required. On the other hand, more unusual potions will require special ingredients, but will not require any particular spellcasting ability.
todo: expand Brew Potion
The character can manufacture the deadly black gas called miasma. Creating one 8-oz vial requires as base ingredients 24 oz of animalcule foam (plus what else? one of the acids? TODO), plus 4 months of lab work.
Upon release from its container, miasma will spread to a radius of 20 feet, and will thereafter drift with the wind. Any creature in the miasma will
todo: what does it do? want to make it distinct from Cloudkill and also capture the historical pseudoscientific notion of causing disease. I suppose it just gives you a short-term variation of a disease if you fail a save: maybe a random choice of influenza, cholera, or chlamydia.
The character can manufacture a paste of quintessence, also called aether, the silvery-yellow fifth classical element. 8 oz each of mercury and sulfur, 2 oz of thaumic powder, and 4 months of lab work, are required to manufacture 1 oz of quintessence.
Quintessence embodies the alchemical principle of non-reaction, and has various effects. 1 oz will nullify any poison or potion it is placed into, transforming it into water. If half an ounce is spread on an object, the next time that object has to make a saving throw or check for breakage, it automatically succeeds. 1 oz applied to the skin will give one-time immunity to any spell which causes aging or energy drain; the immunity can be triggered up to 3 days after the quintessence is applied.
Clone (60) (requires Homunculus)
todo: write this
The character can manufacture the blood-red metal, orichalcum. The alchemist must employ both a coppersmith and a silversmith, and all three must work in the lab for a total of 6 months. Each pound of orichalcum requires a pound each of copper and silver, plus 4 oz of cinnabar.
TODO: what should it do?
The azoth is one manifestation of the magnum opus, the great work of alchemy. It bestows youth, returning its subject to the youthful appearance and vitality of an 18-year-old, removing any accumulated penalties for aging. It also adds 5d8 years to their lifespan, and these years will act as a buffer between the newfound youth and the penalties of aging; thus the aging penalties will not appear until after those extra 5d8 years have passed.
todo: azoth recipe
The alkaheset, the universal solvent, is one manifestation of the magnum opus. Three drops will cause any nonliving object or creature of up to 50 lbs per level of the creator to dissolve and be utterly ruined. Objects receive no save; creatures receive a save vs. Magic at -5. A successful save by the target means the
todo: alkahest recipe
todo: tighten up the effects
True Philosopher's Stone (100)
The creation of a true philosopher's stone is divided into four parts. These are nigredo, albedo, citrinitas, and rubedo; or, blackness, whiteness, yellowing, and reddening. Correspondingly, large amounts of miasma, quintessence, and orichalcum are combined, along with much animalcule foam, in a process which takes 1 year of extremely careful work to complete, and requires the alchemist to work 8 hours per day in the lab, 6 days per week. The 7th day must be spent in prayer and contemplation. Missing or skimping on a day of work requires a d20 roll, with a -1 modifier for each day which has already been skipped or cut short. A 15-20 indicate the alchemist has successfully cut corners; 12-14 indicates a week's progress has been lost; 9-11, two weeks' progress; 7-8, three weeks' progress; 4-6 indicates a month's progress has been lost; anything lower indicates all progress has been lost.
Once created, the philosopher's stone can perform the function of either the alkahest or the azoth, at double strength (giving double the extra lifespan, or liquifying double the amount of material.) Alternatively, the true philosopher's stone may be used for its most famous function: it can transmute any base metal into any noble metal. In either case, the philosopher's stone will be used up in the process.
todo: tighten up description/effects
The point values after each talent's name is the minimum number of Alchemy knowledge points required before a character can select it at level-up. Points themselves are also gained at level-up, with the exact amount depending on which skill trees a character has selected. I'm still working on the details here. (Credit where it's due: the concept of the sage knowledge system, and the gaining of points and new abilities at level up in this particular interlinked way, are owed to Alexis Smolensk. However, all the work above is my own, as are the particular divisions of knowledge which I use.)
Note: the Clone talent represents a more general goal I'm working toward as I consider sage skills for my world. That goal is to pull certain spells out of the spell lists and turn them into ritual-like effects accessed through the skill trees. Other things this might apply to some day include Cacodemon, Spiritwrack, Gate, Astral Spell and its ilk, maybe some of the higher-level divinations; plus Protection 15' Radius will get modified into something called Magic Circle, which I'd put in the skill trees for demonology and thaumaturgy, as things currently stand.