Intermission: A Recipe for Trouble

Magical potions and salves are a staple of classic fantasy. In addition to providing a convenient way to keep adventurers in play after taking one too many swords to the gut, they make great plot devices and quest hooks (the wizard's guild is in need of two score rabbits' feet and the heart of a dragon), as well as making for more interesting tactical decisions. Do we use the invulnerability potion now, or later? Do I poison my arrows with demonbane or spider's venom? Though these considerations usually won't make up the core of a party's tactical repertoire, they can provide a little extra boost to a party in a pinch, and can provide a way for weaker party members (or enemies!) to stay helpful even without fireballs and greatswords. 

Faced with such utility, the alchemically inclined player might want to have a go at brewing their own elixirs. There's plenty of precedent for it in video games such as Skyrim or The Witcher; GURPS Dungeon Fantasy alludes to it obliquely in rules about collecting monster bits, and template skills like Alchemy and Herb Lore, and there's abstract rules for making "bush potions" in DF16 - make a Herb Lore roll and Bob's your uncle, here's a 2d healing potion in a pinch. But being so abstract loses a lot of the charm of alchemy, at least in my mind. I don't want to have a big bag of Alchemy Ingredients, $300, 2lb: I want to mix a pinch of ginger root, a bugbear's spleen, and milk of redgrass! So, should we expand the alchemy system? Why wouldn't we do that? And will I go insane writing it? Let's find out. 

The Good

• Self-directed adventures and side journeys
• I consider this a positive; more story-inclined GMs might disagree, but I love to see players create, adjust, and execute plans all on their own in response to the scenario. The party know they'll be fighting ogres, so they take a quick detour to a nearby grotto to find the missing ingredients for some ogrebane. 
• More player engagement with the game world
• Every GM has experienced the heartbreak of reading out a beautifully written description of a room, just to have the players boil it down to how many doors, how many monsters, and how much loot. Suddenly, all the moss on the walls matters. If the alchemist needs some willow bark, or hawkmoth wings, they'll go looking for it. 
• Higher player skill ceiling
• This is a slightly tongue-in-cheek name for it, but there's real value in players learning the rules of the game world: that blisterwort is found in humid caves, or that wolf livers can save your life in a pinch.
• Collecting things is fun
• Fundamentally, collecting a loot stash is the purpose of a dungeon crawl, but the value of most things found in a dungeon is denominated in $. X goblin swords, Y shortbows, Z gold pieces, and a partridge in a pear tree - and when it all gets back to town, it gets converted into things we want, at a more or less fair exchange rate. Alchemical ingredients are more like the lottery scratch card of loot: weed A is worthless on its own, but if we find fungus B, and we manage to extract the eye of monster C properly, we've made a potion that could turn the tide of the boss at the end!

The bad

• Long player item lists
• I'm fairly indifferent to this, personally - I consider the age-old tradition of "I don't know what to do, let me turn out my pockets and see if I have a gubbin that will improve the situation" to be a positive one. But I can see the difficulty, especially with pen-and-paper gaming, of writing down a hundred and one different ingredients. 
• Risk of exploitation
• Players are incredibly good at cutting right to the bone of a situation; I'm always impressed by the efficiency with which the average party identifies the equilibrium point between cost and benefit. If it's profitable to collect goblin eyes, there are parties that will genocide the local population of greenskins without a second thought - whether that profit is in combat efficiency (if we always keep this ingredient with us, we become more effective) or in trade (we can make potion X in huge quantities and sell it for big sacks of cash).
• Risk of being ignored
• The inevitable flipside of the above is that if the cost-benefit calculation flips the other way, players simply won't engage with a mechanic. If the record keeping is too onerous, or the effects too weak, why bother? 
• Higher GM skill floor
• To gain any benefits, the players must have knowledge and be able to act on it - and that means consistency. The environment needs to be a clue to what can be found in it, and it's false advertising to raise something you don't intend to be in the game. A throwaway mention of blue moss in a cave and the party alchemist realises that he has all the ingredients together to concoct the Dragon Imploder 4000, throwing the final boss battle out of whack. 

Principia Alchemica 

Before making any rules, you should always lay out the intentions and the red lines: what is it supposed do, and what is it not supposed to do? 

An advanced alchemy system should be: 

• Fun! It should encourage creativity and be fast to adjudicate. 
• Rewarding, for those who engage with it.
• Consistent, both internally and with other game rules. No getting 16 lb of dragonbane bile out of a quarter-pound quantum squirrel. (Going in the bestiary, that one.)
• Accessible. It's no good making these rules if no-one is going to use them!

So, considering these guidelines, let's jump right in. 

Alchemy or Herb Lore?

Alchemy and Herb Lore are both IQ/VH skills, available on-template to the Wizard and Druid, respectively. Alchemy, but not Herb Lore, is also available to the Artificer, the Scholar and the Mage-Slayer. It stands to reason that Alchemy should be the primary skill. Herb Lore can stand in for it if only using herbaceous ingredients. Naturalist and Survival are explicitly about knowing non-magical properties, but in a magical world would logically have at least some exposure; they can be used to collect ingredients, but not brew potions. 

Collecting materials

Alchemical ingredients can be collected from monsters, or from the environment. 

Monster ingredients

Our guidelines here come from Dungeon Fantasy 2 and 8, summarised as:

• Extracting toxins requires Poisons, if mundane, or Hazardous Materials (Magical) if not.
• Knowing what's valuable requires a Naturalist or Physiology roll for mundane parts, or Thaumatology for magical ones. Taking external parts needs a Survival roll; anything more fiddly than "gut the thing and drag the innards away" needs Surgery, instead. 
• Harvesting organs takes 30 minutes, with penalties for damage dealt, particularly to the vitals. A success gets you pounds of body parts equal to the margin of success, doubled for every SM above 0 and halved for every SM below it. 
• The per-pound price of the body parts is listed as (number of dice in the most powerful attack) + (DR) + (number of advantages), halved for animals, constructs and mundane monsters. 
• For example, a manticore strikes for 2d, has 1 DR, and has 5 advantages, making its body parts worth $8/lb. 

Edit 23/6: I think this needs adjusting to distinguish between "externals" and "internals". Anything claimed with Survival (horns, pelts, scales, claws) uses the value above; anything gained with Surgery doubles this value to represent the increased difficulty of obtaining it. Thus, manticore teeth are $8/lb, but manticore heart is $16/lb. 

Environmental ingredients

Many alchemical ingredients can be found in the environment. These might be from plants (including mosses and mushrooms), or from other living things that don't qualify as monsters: insects and fish, for example, might be used directly, or you might want their honey or roe. 

• Any of these things can be identified with Naturalist, and harvested with Survival; Herb Lore will work, for plants only. Looking for a specific ingredient adds a -5 penalty, and might be impossible, depending on location. You can't find nettles on the seabed. This penalty can be waived - and even inverted - if the party has gone to a specific location to find that ingredient.
• The ingredients themselves might be intentionally placed by the GM, but be reasonably generous if the players decide to take a look around. In fantasy, strange flora and fauna can be found in the most unlikely of places, which can add a lot of flavour to the world!
• Searching for ingredients and preparing them for use or storage takes 30 minutes, and takes bonuses for foraging modifiers. A success gets you ounces of ingredients equal to the margin of success (16 to the pound, for those of us used to metric measurements). 
• Base price is $1/oz, halved in a "mundane" area, or doubled in an especially dangerous or magical one. The price is further doubled if harvesting the goods is hazardous, for whatever reason - bees and poison ivy are classics, but anything that makes a loud noise or foul smell to attract real monsters would work as well. 

See the appendix for a discussion of names of common ingredients. 

Storing the ingredients

As mentioned in DF8, monster bits go bad at a rate of 1 lb/hr. This can be prevented with a daily roll against Housekeeping or Alchemy. The same applies to environmental ingredients, but being less liable to rot, it's only 1 oz/hr. The preservation roll can be waived by spending a day to dry the ingredients over a fire. This halves the weight of the ingredients, but quarters their value; it's just not as good as fresh. 

Using the goods - what's in the pantry?

These rules allow us to put bounds on what an alchemist might reasonably have access to. An alchemist on his own might have up to 10 lb of ingredients, which could have a value of up to $640 if it were all the highest tier of fresh environmental ingredients. This is an upper bound: upwards of 30 foraging sessions, all finding rare and dangerous plants. $100 to $200 is more likely. Get a barbarian or a pack mule (but I repeat myself) and you could carry maybe 5x that, but that would of course take a longer time to accumulate. 

"So what's the point? That's worth like a 1d healing potion!"

Well, there are two things that make concocting your own potions worth the effort:

• The cost of "standard" potions and poisons is inflated by the Alchemists' Guild and their stringent quality control measures. Material costs make up only a quarter of the price, bringing minor healing potions and cheap poisons equivalent to monster drool very much in reach ($30 worth and $5 worth of materials, respectively). 
• The effective value of materials depends on what you want to do with them. The GM may decide at the point of use if an ingredient is unrelated (x0), related (x1), closely related (x2), or ideal (x4) for the intended use case. Note that a single ingredient does not a potion make; alchemy is about combining!

For example, Ed the Barbarian is face-down in a pool of his own blood (again), and we need a healing potion, stat. The alchemist looks in his bag and finds: 

• 3lb of dried basilisk liver ($5.50/lb), ruled to be unrelated;
• 8oz of healwort ($1/oz). The name makes it ideal, so worth $32 in total;
• 6oz of fire bee honey ($2/oz). Honey's an antiseptic, so related for $12;
• and 4lb of fresh bull demon blood ($12/lb). Bull demons are very hardy; the GM calls this related, for a total of $48. 

The grand total is $92, or just about enough for three doses of 1d healing potion. The alchemist could also try for a single 2d healing potion instead. 

Edit 23/6: When you introduce a magic component, it's a good idea to note down where it was found and any properties you decide for it. This helps maintain consistency.

Microwave Dinners for One

Actually concocting the potion needs access to water, and takes an hour (adjusted for time spent) and an Alchemy roll at -2 with a backpack alchemy lab (but see Appendix B), or an unmodified Herb Lore roll if all of the ingredients are herbal. A further penalty applies depending on the total value of the ingredients used: +0 for $1-25, -1 for $26-50, -2 for $51-100, and so on, taking an extra -1 for each doubling. The GM rolls in secret; the results of the roll are as follows: 

• Critical success doubles the effect of the potion or poison. 
• Success produces the concoction as listed. 
• Failure produces a potion that appears to work but has no effect. 
• Critical failure inverts the effect; a healing potion damages, while a poison invigorates. 

The potion can be used immediately, and has no market value. 

Conclusion

Hopefully this has achieved most of my goals: it's mostly using the original rules, is easy enough to remember and fast enough to adjudicate, and encourages engaging with the game world to look for ingredients as well as creativity from the players and GM. I don't think it's especially exploitable; going mushroom foraging in the woods outside town won't make you rich at $8/day, and it's hard to accumulate huge amounts of ingredients and cook up some bladeblack. Could do with a little more consistency, but that would add a huge amount of bookkeeping for not a lot of results. 

Appendices

Appendix A: The Delver's Guide to Foraging

The naturalist GM probably already knows many plants that can be cribbed from either real life or from video games to add a bit of flavour. Folk names of common plants around the world are a goldmine of this kind of thing; foxglove and hornwort, buttercup and stinkhorn. Insects and fish also have many fun, folksy names: fringeheads, lumpsuckers, earwigs and toe-biters.

But the point of this essay isn't to encourage you to memorise botanical almanacs, it's to have fun, and what's more fun than mad-libs? So here's some guidelines for making ingredients up on the spot, and hopefully combinatorial explosion will do most of the work for me. Remember that once you come up with a name, it colours what the ingredient will do when it gets down to the alchemy, so consider giving names that reflect what properties you want it to have. Or don't, and let the players roll Naturalist or Herb Lore to find out later!

Start with the type of thing you're describing:

• Plants often have names that end in -root, -cress, -weed, -wort, -flower, daisy, nettle, or fern. Modifying trees can be good in a pinch too - there are already a dozen variants of ash tree, why not add another?
• Mushrooms can be of a number of types; polypore, amanita, fungus, bolete, puffball, -cap, chantarelle, bonnet, cup, pholiota, brittlegill. Especially dangerous mushrooms have names like "destroying angel" or "weeping widow".
• Insect names are fairly simple, in the round: fly, ant, beetle, bug, cricket, moth. Suggesting its behaviour (hopper, leaf-miner, flesh-borer) is traditional. 
• The variety in fish names is, quite frankly, huge, and I suspect made up entirely for the purpose of confusing non-fishermen. Many end in -fish, which is nice and easy to remember, but don't neglect anatomical names (bigeye, bonytail, dottyback) or modifying the names of fish that everyone knows: snapper, cod, mackerel, pike, goby, eel, smelt.
• Small animals can be a treasure trove as well. Rats, bats, and newts are traditional; try to stick to vermin if you don't want the local pet population taking a nosedive. 
• Lichen and mosses deserve mention as well, although they rarely vary as much. 

Modify with location, appearance or otherwise:

• The location can be hugely helpful. Suggest cold with ice, snow, or glass; rocks with rock and stone; darkness with black, or blind, or cave; heat, with fire and brimstone and sulphur. Water- is a common prefix, as well.
• Just the colour can add distinction. Red snappers are different than blue snappers!
• Texture is hard to beat for immediate impact. Slimy, thorny, bearded, bony, hairy, woody, fuzzy, and shiny are all fun to imagine getting on your hands - or dropped down your collar.
• Throwing in a possessive can change the feel of a name entirely. Ingredients named after saints, kings or good people imply healing, protective or antidote properties (Saint John's oak, King Henry's Grace, old man's nettle), while negative names do the opposite (devil's thorn, Black Prince's willow). A fool's plant can throw people off. 
• Edit 23/6: prefixing with another organism can be a great way to imply certain properties. Trollroot, mistletoe fly, red rat fungus... the combinations are endless, and get you thinking about what they might have to relate them. 

Finally, don't neglect the product you're harvesting. A handful of firefern is great; a vial of oil of firefern is even better! Plants might have roots, saps, oils, milks, seeds and petals; vermin can have eyes, or wings, feet, eggs, or tails. Fish might themselves have oils, scales and fins, but lay eggs as well - icefish roe is great for frost resistance potions - as do insects, which also often have wings, antennae, husks, galls, stingers, honey, wax...

Hopefully, armed with these, you'll have a much wider repertoire of alchemical ingredients to go forth and stock nature's bounty with. Watch your alchemist's face light up when you tell him he's found 4 ounces of woolly stone-cracker fly wax!

Appendix B: We Need to Cook

Normally, brewing a potion with the backpack alchemy kit suffers a -2 penalty. Buy that off with the following technique: 

Field Alchemy Training (Hard)

Defaults: Alchemy-2; 

Prerequisite: Alchemy; cannot exceed prerequisite skill.

Practicing outside of lab conditions has given you a knack for measuring, pouring and mixing in the field, letting you use a backpack alchemy kit to brew potions at full skill.