Playtesting Alchemy

12 Sep, 2026

I like the idea of having players make their own tools. I also like alchemy conceptually; somehow the appeal of brewing potions out of leaves and mud has stuck with me since childhood.

Naturally, I wanted to bring this fantasy to the table, so the other day I playtested some freeform potion-making rules. This borrows heavily from Naively Simple Alchemy by Rook of Beyond Foreign Planets.

Introduction

As you surely already know, potions are magical liquids that provide a temporary effect upon consumption. Below are some lesser-known facts about potions that may be useful to you.

• Tasting one drop of a potion is enough to determine its properties, and is almost always harmless.
• Consuming less than one half of a potion will have no effect; this makes it essentially impossible to subdivide a potion.
• Not all potions are imbibed; some may be rubbed into the skin, others poured onto the subject, and so on.

Mixing Reagents

Potions are created by mixing Oils and Powders (Reagents). Most anything can be processed into a Reagent using alchemical equipment, distilling it down into its purest essences. A potion’s effect is derived from the properties of its Reagents.

Oils provide the modifier, describable by a single adjective. Powders provide the base, describable by a single noun or verb.

For example, Blink Dog Oil provides “Capricious”, and Bling Dog Powder provides “Teleport”. A potion made by combining the two has the effect “Capricious Teleport”, causing random teleportation.

Import

All things have an Import: Trivial, Mundane, Notable, Extraordinary, or Mythic.

Trivial things are so common as to be found almost everywhere & obtainable with little effort. Grass, water, stones, ants.

Mundane things are common but regional, or require some small expense or effort to obtain. Most things a peasant owns are Mundane. Roses, ale, shoes, seagulls.

Notable things are somewhat rare, expensive, or require special expertise to obtain. Most things a noble owns are Notable; most magical things are at least Notable. Old oaks, acid, jewelry, swords, horses, fairies.

Extraordinary things are rare and special. King collect Extraordinary things. Golden crowns, ships, griffins.

Mythic things are comparable with very few others in the whole world. Even a great emperor would be lucky to have one. Ancient dragons and the like.

Potions of greater Import have more dramatic effect. A Reagent inherits its Import from its source. A Potion’s Import is equal to the lesser of its constituent Reagents’s Imports; as such, if you want a high-quality potion, you must use only the highest-quality Reagents.

See the table below for the typical scale associated with each level of import.

Creating Reagents

As previously discussed, most anything can be processed into a Reagent using standard alchemical equipment; creatures, plants, minerals, tools, and so on.

Creating a Reagent is an uncomplicated but laborious process; at least a day of work, or more if processing something large.

Perhaps unintuitively, no matter how large a thing is, it cannot produce more than one Reagent when processed as a whole. A part of a thing will be of lesser Import than the whole, and its Reagents may have different properties. For example, Oil from a goose (Aggressive, Mundane) will be different to Oil from goose feathers (Soft, Trivial).

Alchemists are encouraged to compile an almanac to record the properties of Reagents as they are discovered through experimentation. Some well-known Reagents are recorded below to get an aspiring alchemist started.

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The Playtest

The scenario was essentially: "You've stumbled across a disused alchemy lab with a handful of stuff to make potions from; go make some potions & plunder the dungeon nearby." I didn't actually give them the text of "Alchemy Essentials" above, as I expected my players wouldn't read it; instead, I gave them a summary. We used Maze Rats as the base system, but the rules above should more or less plug into anything.

To tell you the truth, the playtest could've been better! My players are the type to agonise over decisions; they spent a lot of time discussing what they could do, but only ended up making like 3 potions, and used only 1. Maybe this was just a mismatch for my group, but I wonder if it would have gone better if I'd also given the players a list of common items & their known properties.

Also, I wonder if I might find it tricky to turn the Adj + Noun/Verb into a potion effect. I don't have this problem when adjudicating random spells in Maze Rats, but it's different here because I would expect a potion to affect the person who drinks it, which is an extra constraint. Suppose you have a wand of [rolls up some random words] Slimy Wealth, I think that's straightforward- you cast the spell & get a pile of gross coins, or make some existing coins gross. But what does a potion of Slimy Wealth do to you? Maybe it turns you into a pile of gross coins. Nothing else obviously jumps out at me. In the playtest, I found myself defaulting to this sort of effect- they made a potion of Glass Vessel that effectively turns you into a human-shaped, animate glass bottle, and a potion of Brutal Blade that turns your arms into nasty swords. I wonder if most potion effects would end up being some form of unpleasant polymorph. If I play this again, I might try reframing it as the Adj + Noun/Verb being a spell which the potion lets you cast. This wouldn't be without precedent; a few of the OSE potions give you psychic powers, and D&D 5e has a Potion of Fire Breath.

I'd like to playtest this again, but this feels like something that would be better with longer-term play, as the players fill out an almanac & hunt down ingredients to brew just the potion they need. Unfortunately I've got too much other stuff I want to play; I don't see myself giving this the longer-term playtesting it'd need, at least not anytime soon.

If you would like to use these rules, here's some extra material that might help.

Import Guidance

Use the entries in the Import table above as benchmarks; for example, any effect that covers an entire room should usually be of at least Notable Import, even if its effects are mild. Do adjust if it doesn't feel right; by a strict reading of these rules, a potion that lets you cast Fireball once (damage equivalent to an explosion) would be Mythic, which probably isn't right.

Here's a start on your almanac.