Most old-school D&D retroclones and similar RPG systems don’t have a crafting system, but players often love such things. Here’s a simple way to add one to your game. The mechanism is based on the classic code-breaking game Mastermind. The popular Wordle is the same game but with words.

First Things First

A wizard or artificer wants to create a spell or item that the GM approves as level-appropriate. As a general rule, the character should be at least three levels higher than the spell or character meant to use the item. That is, a 9th-level wizard could create a 6th-level spell or an item appropriate for a 6th-level character.

The character must have the necessary skill, materials, and location (workshop or laboratory). As GM, you may decide what components are necessary for a potion, for example. The Heroes of Adventure Monster Compendium is a great resource for harvesting monster parts for crafting or sale.

The Crafting Test

The GM identifies the 10 or so components for the task, two or three of which are certainly used and the remaining eight are in question. Of those eight, only four are actually used. So the final process might take the form of “2-4-5-1”. No component should appear more than once. It’s not necessary for the numbers to correspond to specific components, altho you can choose to do that for more flavor.

The character must put the right 4 components of 8 in the right 4 positions to succeed. Each incorrect guess gives the character clues about which components are right, which are wrong, and which are right but in the wrong position.

However, each incorrect guess is also likely to produce a minor wild magic effect. The character can avoid this with a successful intelligence check. But after 5 incorrect guesses, the project is a failure.

Components

For a spell, the components might be something like powdered bone of a magical creature, the blossom of a rare plant, a toadstool from a fairy ring, but also verbal incantations and somatic gestures (the exact nature of which is immaterial*). Some material components can be bought, but one or two should be side quests.

For an item, the components should all be materials and require two or even three side quests.

* The hand-waving can be hand-waved. 😉

Example

Jesper wants to create a pair of magic arrows he calls +1 arrows of entanglement. On a hit, a two-legged target of small or man-size or less must check dexterity or be entangled and fall down, requiring 1 round to regain its feet. The GM agrees that a pair of such arrows is reasonable and that they can be shot at different opponents.

The GM decides the components should be:

• A small amount of refined mythril for the heads
• Three shafts crafted of livewood
• Feathers of a falcon
• A small amount of giant spider silk
• A bluebird’s tongue
• Nobrin moss
• Fulgar root
• Incorian leaf
• Lobis tree sap
• A few quillon berries
• A few pine nuts

The livewood, spider silk, and lobis tree sap will have to be found by the character, but the others can be purchased. Gathering these, the character has the arrow made by a master fletcher and then spends some time working on the enchantment. Each attempt should take 1 full week of research and practice.

The character decides the first attempt will be 2-3-1-6 out of 8 components. This is a pure guess. The correct answer being 2-4-5-1, the GM replies that the 2 is right, the 3 is wrong, the 1 is right but in the wrong position, and the 6 is wrong. The player rolls an intelligence check and passes, thereby avoiding a minor wild magic effect.

The player’s next attempt is 2-1-4-7. The reply is that the 2 is right, the 1 is right but still in the wrong position, as is the 4, and the 7 is wrong. This time, the character fails the intelligence check and suffers a minor wild magic effect, but attracting harmless frogs until the next full moon won’t delay the experiments.

The player’s next attempt is 2-4-8-1, and the tantalizing reply is that the 2, 4, and 1 are right but the 8 is wrong. The character passes the intelligence check.

Now a bit giddy, the player’s next attempt is 2-4-5-1, which is entirely correct, and the process is a success! The arrows of entanglement are complete!