OSR: A Material Component Magic System

Material components are annoying. They're fun in theory but a pain in practice.

Most groups operate on the time-hallowed system of tracking only components with a substantial cost (e.g. the 100gp pearl for identify) or simply deducting their cost from a character's cash. Some GMs keep track of rare components, like vampire dust or basilisk eyelashes, but most don't.

Single-player resource management minigames aren't fun. You can write material gathering encounter tables and eccentric shopkeepers, but it's difficult to make material components interesting for an entire group, unless the entire group is into it. Helping the wizard gather mushrooms and bat fur usually feels like a distraction from the game at best or a monopolization of spotlight time at worst.

But what if material components weren't an addition to a spellcasting system? What if they were the core?
Filipe Pagliuso

Canon Components

In AD&D, the main wellspring of the concept, material components fall into two categories:

1. Sympathetic Magic:
  • Protection from Normal Missiles: piece of tortoise or turtle shell.
  • Summon Shadow: smoky quartz
  • Grease: bit of pork rind or butter
  • Detect Undead: pinch of earth from a grave
  • Wall of Stone: small block of granite
  • Wall of Fire: phosphorous*
2. Gygax's Little Jokes:
  • Wall of Fog: pinch of split, dried peas. => pea soup fog
  • Message: short piece of copper wire, drawn fine => telephone wire
  • Ventriloquism: parchment rolled into a cone. => megaphone
  • Confusion: three nut shells => shell game
  • Passwall: pinch of sesame seeds => open sesame
And of course the ridiculous items and actions required to cast Tasha’s Uncontrollable Hideous Laughter.
*Incidentally, in the real world, phosphorous was discovered in 1669, which is a bit odd for a medieval-ish D&D setting, but so it goes.
Glendower: I can call the spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;

But will they come, when you do call for them?
- Henry IV, part 1. Act 3, Scene 1

The Blackmoor Magic System

The system used in Arneson's Blackmoor campaign remains shrouded in mystery. There are a few hints in The First Fantasy Campaign, and but not enough to completely reconstruct the system. It was very material-heavy.
In Blackmoor, magic followed the "Formula" pattern for most magic. The reasoning behind limiting the number of spells that a Magic User could take down into the Dungeon was simply that many of the ingredients had to be prepared ahead of time, and of course, once used were then powerless. Special adventures could then be organized by the parties to gain some special ingredients that could only be found in some dangerous place.

Progression reflected the increasing ability of the Magic user to mix spells of greater and greater complexity.
-The First Fantasy Campaign
It's possible that the system defies systematization. If it was a collection of ad-hoc rulings for every effect, writing it down for publication would be impossible.
Sam Carr

Towards An Alternative Casting System

What if, instead of being being a requirement to cast a pre-written spell, material components are the spell? The caster holds two items, fixes their mind on a belief, and convinces the universe to "make the world like this."

Say a Magic-User wants to cast a spell to clean their house. They might grab bristles from a broom and a flake of soap and say "make this house like this." Or they might grab a tin whistle (for "as clean as a whistle") and a square of paper (for "squared away").

If you want to charm a monster, put a bit of sugar on a coin.

The spell has to convince the universe and the GM. The player has to be confident that the items will produce the effect. That's the point of being a wizard.

This is a different approach from otherfreeform magic systems like Whitehack or Maze Rats. There's no table of suggested effects or spells. Instead, the Magic-User's player goes through their imaginary pockets and cobbles together an effect based on poetic logic. It's similar to Nick S. Whelan's magic word system, but with objects instead of abstract concepts.

Material Spellcasting

'Witches just aren't like that,' said Magrat. 'We live in harmony with the great cycles of Nature, and do no harm to anyone, and it's wicked of them to say we don't. We ought to fill their bones with hot lead.'
Wyrd Sisters, Terry Pratchett 
This system should drop into old-school games without too much trouble. There's noo need to rewrite the entire game.

Whenever a Magic User would gain a spell slot, they instead gain 1 Magic Point. To cast a spell, the Magic User selects 2 material components and spends 1 Magic Point. The materials are consumed. The caster must hold the materials and speak a few magic words. Magic points are restored each day, just like spell slots.

The player describes the intended effect to the GM, and why the chosen materials will produce the effect.

"I want to set all of them on fire. I'm going to use some of the skin of that fire toad we fought last session and some flour."

"I want to transform into a bear. I'm going to use some bear fur and some clay."
GM is free to dispute or refine the effect.
"I want to set all of them on fire. I'm going to use a candle and a bit of string."
    "How exactly will that work? A candle burns pretty steadily. And what does the string do?"

          "I want to lock that door. I'm going to use some sealskin to seal it and some mortar."
             "That feels like it would fuse the door to the frame, not lock it."
           "Fine by me!"

"I want to drive that monster into a frenzied rage. I'm going to use wax and a thorn."
    "Ok... explain?"
"To wax wroth, and to be nettled."
    "Damn it, that's awful but it works."
After casting a spell, the player notes the materials and effect and materials a spellbook, then rolls 1d6. On a 3+, all future casts of the spell cost +1 Magic Point. This is cumulative. (This chance may need to be adjusted after additional testing.)

A Magic-User cannot create an identical effect with different items. Once a Magic-User does something one way, that's how it's done. That's their house-cleaning spell or the fill-bones-with-hot-lead spell.

A Magic-User can share their method and items with another spellcaster. The base chance that the other caster will be able to use the spell is [caster level]+50%. The first time the caster uses a learned spell, it costs 1 MP as normal.

A Magic-User can keep up to 20 materials (different or duplicate) ready for instant use. They can store more materials in a pack or pouch.
(This may need to be adjusted after additional testing, but twenty items seems like a good number without being overwhelming.)

A Magic-User cannot level up until they've cast a total number of unique spells equal to current level's spell slots. This shouldn't be a problem.

Most of the time, a Magic-User cannot invent new spells during downtime or non-adventure situations. Spellcasting requires a heightened emotional state. Use the rules for spell research for downtime testing, especially if the player has a desired effect in mind. The point is to avoid, "I have 3 days of downtime and 5 Magic Points, so I will invent 15 new spells." Instead, gather material components during downtime.

Like this, but fancier.

Spell Effect Guidelines

This system assumes the GM has a reasonable grasp of spell effects and mechanics. It's an advanced and personalized system.

Creatures still get Saves.

Use [caster level] to adjust the power of spells.
  • Fireball. 1d6 per [caster level] in a 20' sphere. 
  • Fly. Fly for 1 hour + [caster level]x10 minutes.
  • Charm Monster. Charm up to [caster level] x 2 HP of monsters for 1 day.
  • Transform for [caster level]+1 rounds.
Material components must be plausible medieval-ish items that the caster can obtain or gather without too much trouble. Good luck keeping ice chips cold in your pocket.

Rare items produce a stronger effect. The heart of a unicorn and a diamond the size of an apple will probably bring someone back to life, but players are unlikely to have a renweable supply of unicorn hearts. 
A candle stub and a bit of flint will produce a mediocre light spell, closer to a cantrip than a proper spell.
You could make the spell cost HP as well as Magic Points, but only in systems with fast healing.


Magical Thinking

This system relies on associations, allusions, fuzzy logic, magical thinking, and puns. Dictionaries of idioms and quotes might help. Real-world books on the magic properties of herbs and crystals don't; since their magical effects have to be indistinguishable from chance. This list of alchemical reagents is a good starting list of items.

Here are a few examples of material component associations. It's not a complete list, just food for thought.

Organization. Summoned by a bell, saved by the bell.
Announcement. Wedding bells, alarm bells.
Clarity and purity. As clear as a bell.
Doom. For whom the bell tolls.
Memory. Rings a bell.
Fanciness. Bells and whistles. With bells on it.

Mortality, time, aging.
Depth, possibly hidden. Soaked to the bone, feel it in my bones.

A funeral shroud.
A blindfold.
A napkin, as in a magic trick.
Muffling. Cloth ears.

Blinding, sneezing, impairing.
Worthlessness. To shake the dust from your feet.
Death. To bite to dust, dust to dust.
Hidden things. Dusting for fingerprints.

Graveyard earth, hallowed ground.
Native soil.
Distance. Four corners of the earth.
Sensibility. Groundedness, to come back to earth.
Materiality. To move heaven and earth. Older than dirt.
Secrets. To have dirt on someone, to dirty one's hands.

Enclosing, hatching, possibilities, new life.
Transformation, growth.
Zero. A goose egg.
Wealth. The golden egg.

Aspects of a creature.

Honeyed words.
Attracting animals and insects.


Toughness. Health and resilience. As tough as old leather.
Hardness, hardened skin.

Sticky, but mild.
To wax wroth, to wax lyrical, to wax and wane.
Trustworthy. Wax seals.
Secrecy. Sealed letters, none of your beeswax.



This system lets a Magic-User potentially solve X problems per day.

If they encounter more than X problems, the Magic-User can cast the classic spells "mundane missile", "cower", and "bluff."

Fighters solve one class of problem, Clerics solve a narrow class of problems and help fix failure to solve other problems, Thieves go around the problem or give everyone time to plan, and Magic-Users frequently trade one problem for a different problem.

This system enables extremely flexible casting, at the expense of reliability and power. In this system, creating an effect as powerful and as persistent as the 9th-level spell bigby's crushing hand would require more than an eggshell and some snakeskin.

It also encourages players to interact with the world, to hoard wizardly items, and to think outisde the box. Save up your weird wizard treasures for powerful one-off spells. 

The spellbook also serves as a campaign record. "Remember when I put all those goblins to sleep using sand and lettuce? Good times." "Yes, but the bugbear still broke my arm." "Good times..."

The total number of Magic Points is pretty sensible. A player might try to maximise their Magic Points by only casting unique spells, but most of the time, effects they've already produced are too tempting not to use again. The table below is from AD&D.  

A player might invent fireball or finger of death at level 1, but each cast potentially increases the cost. They might not even be able to cast it a second time until level 2.

Spell Level

Level 1 2 3 4 5 6 7 8 9 Spells
1 1                 1
2 2                 2
3 2 1               3
4 3 2

5 4 2 1

6 4 2 2

7 4 3 2 1           10
8 4 3 3 2           12
9 4 3 3 2 1         13
10 4 4 3 2 2

11 4 4 4 3 3

12 4 4 4 4 4 1

13 5 5 5 4 4 2       25
14 5 5 5 4 4 2 1     26
15 5 5 5 5 5 2 1     28
16 5 5 5 5 5 3 2 1   31
17 5 5 5 5 5 3 2 2   32
18 5 5 5 5 5 3 3 2 1 34
19 5 5 5 5 5 3 3 3 1 35
20 5 5 5 5 5 3 3 3 2 36

Sidebar: Divine Casters

Clerics don't use this system. They get their spells normally. They don't need to convince the universe, they just need to manifest the will of their god.

Alternatively, for each spell slot, the Cleric rolls on a random holy verse table (using the book or books of your choice, but using all the verses, including the boring ones.). The spell's effect depends on the verse or line. Each day, the Cleric may replace any number of lines/spells or keep previously generated lines/spells.


  1. I find this delightful, but as the wizard's carried reagents are limited, so too are the number of players in your immediate area who are clever enough to 1) use this and 2) enjoy it. As above, so below.

  2. A very pleasant system, it would pair very well with my alchemy rules.

  3. Sounds fun but by experience i avoid like the plague every magical system that relies so much on negociating with the GM. I like the concept but the spell effects for me must be set clear a priori, or will be highly conditioned by the GM wanting to help (or kill) the PCs; while any bargaining at the table is always a huge turn down for everybody present.

  4. This sounds like it could be entertaining with the right group, but I worry that players already have a tendency to get bogged down obsessively investigating minor items they encounter, and that this is going to increase tenfold when literally anything could be the key to a powerful spell ("so you say the room contains nothing but a drawer full of cheap cutlery? Guys, should I take any of these? What metals are they all made of? Let's brainstorm all the spell effects that could potentially be associated with 'spatula'.") Things could also get bogged down at the spell creation stage ("no, no, I'm sure I can make a spell to solve this exact situation. Let me just run through my list of 20 components and make a start on reviewing the 380 potential combinations"). Therefore, I propose an amendment whereby - in keeping with the fundamentally spontaneous and mystical nature of spellcasting via this method - spells can only be created using items and substances that are to hand in the caster's immediate environment, and not with anything that they've carried with them. Thereafter, they can take the ingredients with them and restock them as normal, but that first moment has to be "OK, so I can see some luminous mushrooms, a rusty mantrap, and the corpse of the goblin we just killed; let's see if I can improvise a way past that owlbear..."

    1. You're correct in that it's very group/player dependent. But I've been known to be fairly merciless when it comes to turns and decision paralysis. If a player wants to clarify something or get more information, that's all fine, but if it's their turn and they're taking too long, I've sometimes dropped them in the initiative order or even skipped their turn entirely. Pacing is important, and it's the GM's job to set the pace.
      If a player wants to brainstorm, that's all fine and dandy as long as it's on their own time and not the table's time, unless it involves everyone at the table. Start a sidebar or think quietly by all means.

  5. This sounds wonderful, and the general idea seems to be very easy to add onto any ItO-based system. Really clever!

  6. I like how this creates incentives to specialise--if you can carry 20 items in total, you want to try and make as many spells out of those items, so you end up becoming the bell guy or the sand guy or whoever because all your spells are bell + X + Y.

  7. I quite like the way this works out in Whitehack: Magic costs HP. If you go to the trouble of acquiring and using resources like material components for your spells, it's likely to cost less HP.

  8. Are you familiar with Luke Gearings "Wolves Upon the Coast"? A classless osr compatible ruleset lukegearing.blot.im/wolves-upon-the-coast. It doesn't have skills or classes, so to use magic you need to learn the specific spell from a teacher, and have the specific components for the spell. The rules and spells are all free on his site

    It's actually pretty cool. Relies on the pcs activity searching for magic and components.