(English article) So I wanted to make an alchemist of sorts in a D&D game. How to do that? Why is there not a clear way for characters to brew the potions that you see in the Dungeon Master’s Guide, or to create you own? Or is there?

Well, it’s not like it’s entirely impossible to do these things with the rules on the DM’s Guide, it’s just that it doesn’t work. So this is an attempt at presenting a fair and straightforward game mechanic for brewing magic potions and oils in Dungeons & Dragons 5th edition games, and similar d20-based rulesets.

Why the Crafting Magic Item downtime rules don’t work for potions in 5th edition

(This is just for background, skip to my solution if you don’t want to read this.)

Some sparse rules for downtime activities are available in the DM’s Guide, pages 127-131. These rules were expanded in an Unearthed Arcana edition by Mike Mearls and Jeremy Crawford, released for free back in october 2017. Both of these options feature a Crafting Magic Item activity (called simply Crafting Item in Unearthed Arcana) that could, in theory, be used for creating any magic item, including potions and oils. For most items, these rules work just fine.

The problem with the options available in both the DMG and Unearthed Arcana is that the prices don’t add up for potions or oils. Prices are based on rarity alone, which means crafting a one-time consumable very rare Potion of Flying (that allows you to fly in the air for an hour) costs as much as making a very rare Carpet of Flying that will allow you to fly indefinitely and even invite your friends Aladdin and Jasmine to come along, for as long as you keep your carpet safe.

Back in 3rd edition, when prices were fixed for all magic items, you could more easily note the differences in potions and other items’ valuation. A small 5×5 ft. Carpet of Flying had a starting market price of 20 thousand gold pieces, or much more for larger variants. A Potion of Fly would cost 750 gold pieces. In 5th edition, both can be “very rare” items, I won’t argue with that, but there’s a reason one can be worth over 26 times as much as the next: the potion is a one-time consumable, and the carpet can potentially help the character for all his life.

Another little comparison from 3rd edition: prices of potions and oils would typically range from 50 up to 3,000 gold pieces (and note that the effects of the more expensive ones would normally be impossible in 5th edition, as they feature attack bonuses over +3). Other types of magic items (wondrous items, rods, weapons and so on) could cost as much as 200,000 gold pieces or more.

The market price is important because it is a good reference for the cost of crafting magic items. Back in 3rd edition, to craft most magic items, you needed to acquire and use magic materials and reagents worth half of the market price listed for that item in the DMG (along with a cost in experience points). In 5th edition, the intended costs of crafting materials follow the same logic, but because there are no fixed market prices, only broad definitions of rarity along with loose bands of market values that openly disregard the one-use nature of potions and oils (and scrolls of course), the official costs for brewing potions are way off. In both the Dungeon Master’s Guide and the Unearthed Arcana optional rules, as the rarity goes up, brewing a single potion becomes prohibitive.

So, I like the general way crafting is handled simply and ellegantly in 5th edition, but a cost adjustment is necessary for potions and oils. It is also desirable to be able to create and valuate new invented potions. These are my goals in this article.

New downtime activity: Brewing Potion or Oil

During your spare time between adventures, you can attempt to make magic potions and oils to help you when the time arises. That can take a lot of effort, but in time, if you’re good enough, it can be very useful and even turn a profit.

Resources

To start, you’ll need a few things:

• At least one workweek (5 days) to spare
• Properly deployed herbalism kit or alchemist’s supplies along with the proficiency to use it
• The recipe for the potion or oil that you want to make
• Ingredients specific for the potion or oil that you want to make, at the cost listed on the table below
• Proficiency in Intelligence (Arcana) ability checks for uncommon rarity or higher

Rarity	Cost	Workweeks	Pre-requisites
Common	1d4+1 x 10gp	1	Herbalism kit or alchemist’s supplies + proficiency to use it
Uncommon	1d4+1 x 20 gp	2	Arcana + Herbalism kit or alchemist’s supplies + proficiency to use it
Rare	1d6+1 x 40 gp	3	Arcana + Alchemist’s supplies + proficiency to use it
Very rare or legendary	1d8+2 x 50 gp	4	Arcana + Alchemist’s supplies + proficiency to use it

Recipes: To make a potion or oil, you’ll need its recipe, that is, a formula that states what ingredients are needed and how they should be employed. Finding recipes may not be easy, as they are as rare as the potions themselves. Starting herbalists and apothecaries should know at least two recipes (antitoxin and Potion of Healing), while the more experienced ones might know several, although they’ll specialize in potions and oils of common rarity. Uncommon recipes might be found with proper alchemists and well-stocked libraries. Rare recipes will mostly only be found in magic enclaves and colleges, or with established alchemy masters. Very rare and legendary recipes are the hardest to come by, and will probably be treasured and kept secret by whoever owns them. Regardless of rarity, at the DM’s discretion, getting hold of any recipe might require some searching, gold, connections or favors, if they are even known to man.

Ingredients: The base, reagents and materials necessary for brewing each potion and oil will vary wildly from setting to setting. In general, each recipe won’t have much in common with the next, meaning you’ll need to acquire different ingredients for each creation. They might or might not be readily available in regular markets, and will be less available wherever it is as the rarity of the potion goes up. Whatever it is you’ll need, the cost of the ingredients for a single potion or oil depends on rarity and is listed on the “Cost” column of the table above.

Procedure

To make a potion or oil, provided you have all resources at hand, you must get to work for the full length of time required according to the table above. You’ll need to spend at least 8 hours a day working on it for five days to make a workweek. At the end of each workweek, you must roll an Intelligence check and add your proficiency bonus. If the result beats DC 10, you’re successful (and could continue if needed), otherwise you waste the ingredients and no usable item is created. In case you fail by a margin of 5 or more, you get a complication.

Help: With an extra pair of hands, you might be able to get faster or better results. In order to help, other characters will need to have at least the proficiencies required for the same potion or oil you’re creating (according to the table above), and work for at least 8 hours a day like you. A helper will either cut the time needed to finish the job in half, allow you to work on an extra recipe or batch per workweek, or get you a +2 bonus on your Intelligence checks to brewing (your choice). You can have up to three helpers, and no two of them can get you the same bonus. Working on an extra recipe or batch means you need to roll a separate (extra) Intelligence check per batch per workweek.

Batches: If you’re working with alchemist’s supplies, you can brew a batch of up to five potions or oils of the same kind at a time. Multiply the ingredients’ cost by the number of items you’re creating. The time or DC needed to complete the job doesn’t change (and you only need to roll Intelligence checks once per workweek per batch, regardless of how many potions each batch has).

Complications

Every time you fail your workweek Intelligence check by a margin of 5 or more, you get a complication. Roll 2d6, add 1 for an uncommon potion or oil, 2 for rare, 3 for very rare or legendary, then check the table below.

In case you’re working on more than one batch or recipe at the same time with helpers, at the DM’s discretion, some complications might destroy your other work as well.

Roll	Complication
2	This experiment made a sizable mess, and now you’ll take at least an hour cleaning up your workshop to be usable again.
3	Sticky or solid wasted ingredients are all over your herbalism kit or alchemist’s supplies, and now you’ll take at least 3 hours cleaning up your workshop to be usable again.
4	You made a veritable mess with your experiment and ingredients, either burning them too bright or petrifying them in their jars, and now you’ll take at least 8 hours cleaning up your workshop to be usable again.
5	A terrible smell escapes your experiment. While that is not necessarily dangerous, it might draw unwanted attention.
6	Black smoke escapes your experiment. While that is not necessarily dangerous, it might draw unwanted attention, as it does look like a fire from a certain distance.
7	A rack of jars falls to the ground, damaging your herbalism kit or alchemist’s supplies for 25% of its market price. It can only be used again once repaired.
8	A small fire starts on your workshop. While no one should be hurt, you and each person that is frequently close by (helpers, people that live in the same house where the lab was located, etc.) have a 50% chance to be around to put out the fire when it starts, otherwise your workshop could be damaged or even destroyed.
9	An unpredictable reaction, possibly magic in nature, sends an electric arc across the workshop. You and helpers each have a 50% chance to get 2d6 electric damage.
10	A fire starts on your workshop, taking you and helpers by surprise, while also damaging your equipment. You and helpers each have a 50% chance to get 3d6 fire damage, and the herbalism kit or alchemist’s supplies used in the brewing is now in need of repairs worth half the cost of a new kit (and it cannot be used until repaired). If you’re not quick to put out the fire, it might take larger proportions (and if no one received any damage, there’s a 50% chance no one is at the scene when the fire starts).
11	Poisonous fumes escape the flasks and tubes in your workshop, filling the room with toxic smoke. You and each person that is frequently close by (helpers, people that live in the same house where the lab was located, etc.) have a 50% chance to accidentally breathe the fumes and get 4d6 poison damage.
12+	A rare, explosive reaction to your experiment destroys your workshop (herbalism kit or alchemist’s supplies along with other fragile equipment nearby). You and each person that is frequently close by (helpers, people that live in the same house where the lab was located, etc.) have a 50% chance to be in the blast radius at the time and get 5d6 fire damage. Anything flamable nearby catches fire instantaneously (clothes, wood, papers, recipes, etc.). If you’re not quick to put out the fire, it might take larger proportions (and if no one received any damage, there’s a 50% chance no one is at the scene when the fire starts).

New item

Mutus Liber

Rare, 1 lb.

This mysterious book displays engravings that show precisely how alchemical techniques are done and with what equipment, although it doesn’t teach anything to those that don’t already know what they’re doing, because the book has no words, only images. One can only speculate why this book was designed thusly. Maybe the author wanted to avoid teaching powerful and dangerous alchemy concepts to rivals, or to make this manual inconspicuous for the scrutiny of inquisitors and prosecutors of the occult and heretic.

An alchemist brewing a potion or oil with alchemist’s supplies and this book at hand can add double its proficiency bonus to its Intelligence checks at the end of each workweek.

On a low magic setting with a lackness of widespread scientific knowledge or proper libraries and colleges, this book can be very rare.

Potion and oils’ rarity overview and examples

Inventing new potions and oils can be as simple as just picking an effect from a existing spell, but establishing its rarity can be complicated. To help with that, I wrote this overview of the rarity of existing potions and oils along with examples.

Common effects are more or less mundane, and could pass as non-magical in certain settings. They mostly tend to be useful in specific situations on the exploration pillar of adventuring. Examples: instantly healing 2d4+4 hit points; becoming immune to sleep for a night; comprehending languages or making climbing much easier and faster for an hour.

Uncommon effects might give you a certain edge in combat, or classic wondrous abilities. They can be useful in a variety of situations, or make otherwise impossible actions possible for humans. Examples: instantly healing 4d4+4 hit points, becoming charmed by someone else for 10 minutes; getting superhuman strength, resistance to damage from a single element or being able to breathe underwater for an hour; making a character or surface super slippery for 8 hours.

Rare effects can be life-saving in the face of supernatural dangers. These effects might completely change how prepared you’d be against particularly powerful enemies. Examples: instantly curing almost any disease or condition (such as blindness or paralysis); getting resistance to any damage for a minute; becoming completely ethereal as per the 7th level spell or as strong as a fire giant for an hour.

Very rare and legendary effects are maybe hard to tell from rare effects, but they obviously are ranked after their multi-purpose usefulness, normally offering powers that are only possible with spells that require constant concentration. These tend to be the potions that even if not entirely miraculous, you’d want to carry and drink at all times if you could, because chances are you could always benefit from being able to fly or disappear in pretty much any adventure. Examples: instantly healing some 40 hit points, poisons, diseases and even exhaustion (which is hard to do indeed in this game); becoming very fast on your feet and blows for a minute; being able to fly or becoming invisible or as strong as a cloud giant for an hour.

If you look closely, the rarity of potions and oils doesn’t exactly follow the power level of spells they emulate. For example, there are rare effects that emulate the effects of 2nd-level (Potion of Mind Reading), 5th-level (Potion of Mind Control) and 7th-level spells (Oil of Etherealness). In comparison, among very rare potions, there are two or three potions that emulate 3rd level spells (Potion of Invisibility and Potion of Speed). So don’t get too attached to spell levels when creating your own new potions and oils, and use your own discretion.

If in doubt, as a rule of thumb, you should consider niche exploration powers common, specific superhuman powers uncommon, more general combat buffs rare, and multi-purpose utilitarian buffs that help in almost every game very rare or legendary.

How do you like these rules as presented here? Please contribute by commenting below.

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