AD&D Magic System Part 2: MFG

Manufacturing magical items is a big deal. Especially in a game world (like mine) where magic shops don't exist. In this blog post I'll be covering manufacture of potions, scrolls and items (both permanent and expendable) as well as how to recharge expendable items.

The rest of the magic system will come in Part 3, which will cover magical languages, spell research and spell creation.

Let's start with


Making potions is the purview of magic-users. Illusionists lack the breadth of knowledge, and so do clerics. Druids aren't BTB potion makers either but I might allow them to make certain kinds: Animal Control for example. And my house rule is to allow the witch and incantrix to brew just like magic-users. That said, anyone who told me that illusionists should be able to manufacture Potions of Delusion; Invisibility; and Love would get no argument from me...

Brewing potions starts at LEVEL 7 and requires the help of an Alchemist until the PC is 11th.

Here is my spreadsheet calculator for potion brewing (made in excel).


  • Initial Lab Setup Cost

  • Monthly Cost of Lab Supplies

  • Hiring bonus to secure the Alchemist

  • The Alchemist's salary per month thereafter

In this example, the magic-user is 10th level and is trying to brew a potion with an XP value of 400. Therefore the cost of brewing is 400 GP, will take 4 days to brew, and has a success rate of 50%.

If the brew fails, the potion becomes a cursed potion by random roll.

If you want to make your own calculator it's very easy. Regard DMG p116.

Note the optional rules for potion failure on p117 (which I have elaborated on).

My formula runs thus:

  1. Base Chance of Failure = 20%

  2. Divide the XP value of the potion by 10 = 40% (from example above)

  3. Add these together = 60% chance of failure

  4. Subtract magic-user's level = 50%

Voila. This is the formula I use for all potion brewing and it works great in regard to risk/reward and profit. It also makes the very powerful potions quite difficult to brew your mages won't be wandering around w/ every kind of Dragon Control in their Handy Haversack.

My rule is, if you find a potion, you must destroy that potion to get its recipe. Thereafter, you can begin manufacturing. You can also research a potion recipe but that's much harder than destroying a potion to study its ingredients. My method would be to treat such research the same as spell research (covered in Part 3 of this series).

Next up, notice that my potions have reliable descriptions. Here is a sample of my potion list:

This is not BTB for according to Gygax, no two Extra-Healing Potions look alike. Gary did not like players knowing what a thing was or how to it might be used unless money and time were spent each and every occasion. IMO, since Impostor Potions can look like any other potion, risk is high enough to keep players guessing, while the catalog of descriptions encourages players toward the good habit of note-taking.

Let's move to:


Making scrolls is much easier than making potions. I refer you to DMG p117----118. There are two types of scrolls:

  • Spell Scrolls

  • Protection Scrolls

All spell casters can make both types of scrolls starting at 7th level. In my current campaign, there is a LOT of potion brewing and scroll scribing going on during downtime. Gary recommends some pretty nightmarish (albeit atmospheric) stuff for recipes and procedures----most of which I make abstraction of. The intent is good; so I do have certain plants, parts of magical creatures (and so on) that, if collected, will reduce the cost [or] time [or] failure-rates of manufacture. Ergo, the magic-user requests that the ranger cut off the Peryton's horns for him and I will state that one horn is good for influencing one potion [or] scroll in one way (picked from the vectors above). Thereby, we make ingredient harvesting useful, simple and avoid looking up long lists of ingredients in an onerous catalog. Some very rare ingredients might even ensure success for the potion or scroll on which it is used. Note that my methods do not preclude you from role playing a full recipe of strange ingredients and widdershins walking around the church if this is to your liking. My goal here is primarily to give you the mechanics for dice rolls for when the time to determine success arrives.

Let's get to the actual formula for scroll creation:

In this example, the spreadsheet allows (as with potions above) for me to plug in the spell level, the magic-user level, and the material used (vellum/parchment/papyrus). A percentage of success is then spit out.

Chance of Failure is BTB: 20% + 5% (because in this example the spell level is 5) - 10% (caster's level from example) -5% (because vellum) = 10% chance of failure (aka 90% chance of success). Again, you may refer to DMG p117 if you got lost.

Moving on to protection scrolls, you'll notice on p117 that the domains of protection are split between magic-users and clerics. Study-for-it casters cannot craft scrolls from the pray-for-it list and vice versa. At least that's the general idea and I stick to it.

I have expanded the list considerably to account for other types of protection scrolls.

In addition, since protection scrolls are extremely powerful, I wanted a much higher chance of failure (more akin to making a potion) so in order to be able to use the same calculator, I simply put the number 50 into the Spell Level field.

Doing this shifts the chance of success (for a 10th level magic-user to create a Protection from Demons scroll) to 45% and a cost 2,560 GP for the attempt. It will also cost 50 days to scribe. This is, IMO, a great way to limit the number of protection scrolls that the PC can reasonably make while still giving them a path to success.

Note that the formula for making Protection Scrolls is entirely my own, but extrapolates from the approved formula while trying to ensure game balance.

With a spreadsheet, you can quickly calculate the percentile roll for any potion or scroll your Players want to manufacture and tell them both the cost and time such an endeavor will demand.

But what if they actually make it to a level where they can begin crafting more substantial:


Sword manufacture is a different thing. You can delve that topic in the DMG on p166 and extrapolate from my calculator below how you might account for all the variables of swords. I haven't actually had to work out a sword's creation yet, but I reckon I'd start from this here spreadsheet and do add-ons for the various Primary Abilities, Special Purpose/Powers and so on.

Take a look at my template:

In the example above, a 12th level M-U is trying to manufacture a Wand of Fire (XP value: 4,500 & GP value: 25,000). This is a very powerful item. Even with 3 assistants and 100 days of labor (the max) the M-U's chance of success is lower than impossible.

But hey, what about a Wand of Metal and Mineral Detection (XP value: 1,500 & GP value: 7,500)? See below:

In this case, the M-U is able to spend just 80 days with 3 assistants to generate a 96% chance of success.

Note: NONE of this is by the book. This table is my own creation in answer to the foggy instructions for item creation found in DMG p118. Here's the Breakdown:

  • Library GP value (in this case 350,000 GP) x 0.000001 = 35%

  • Final Value of Item (in this case 7,500 GP) x --0.0001 = --75%

  • Days Spent Crafting (in this case 80) x 0.01 = 80%

  • If an alignment is applied to the item it increases odds of success by up to +3 vs keeping the object unaligned which modifies the percentage by --3%

  • Number of Regular Add-on Powers x --0.05 = % chance reduction (DM fiat but compare to DMG p167 Table 3)

  • Number of Exceptional Add-on Powers x --0.10 = % chance reduction (DM fiat but compare to DMG p167 Table 4)

  • If the item will be an Artifact = --50% to success

  • If the item is rechargeable = --1%

  • If the creator is a Pray-For-It type = +5% for clerics and +4% for Druids

  • If the creator is on good terms vs not with his/her deity then +/-- 5%

  • Crafter's Highest Spell-Casting Level (in this case 12) x 0.01 = 12%

  • Crafter's Prime Requisite (in this case 18) x 0.01 = 18%

  • Number of assistants (in this case 3) x 0.1 = 30%

  • Libraries of very high value reduce the manufacturing cost: Library Value x 0.0000001 x Final Value of Item (7,500) = 262 GP discount, ergo 7,238 GP for this manufacturing attempt.

  • Chance to Permanently Lose Con = 5% for permanent magic items (see DMG p46) or 100% if the item will class as an Artifact. (the artifact rule is my own).

  • Recovery time (where the creator can only eat and sleep) is the XP value of the item (in this case 1,500) divided by 100 = 15 days.

So, obviously the crafter's library value is of paramount importance as it provides all the references, formulae, secrets and so on to make success more likely. This is AD&D where GP = XP, therefore magical libraries are fantastic money sinks. Once a library exceeds 1,000,000 GP value, the manufacture of magic items becomes considerably easier for obvious reasons.

Again, rather than delving into the details, I refer you to the spreadsheet where you may experiment with different configurations yourself.

I allow the magic-user to know the chance of success before committing to the endeavor. Thereby, the player can tweak the number of assistants he/she hires, the number of days he/she invests and feel that a tactical choice is being made. If the project has no chance of success, the crafter understands this ahead of time and realizes he/she must buy more books for the library, continue to level and try again later.

In reference to the alignment field specifically, I give a small bonus to the success chance if the crafter imbues the object with his or her alignment because it helps with controlling game balance and implies that the gods are watching such endeavors; making efforts to control who wields them through the whisper or denial of the muse.

With regard to assistants, all of them must be of a level at least half that of the main crafter and must spend the same number of days in both crafting and recovery. How much an assistant costs is a matter of DM fiat. A rate of 25 GP per day per level of the assistant seems right to me.

All of the above should underscore just how difficult magical item manufacture is in my game, but it is possible: especially with a large library full of rare tomes. The spreadsheet handles both expendable and permanent magic items and allows you to cycle the class of the crafter. Get yourself a copy of excel or open the sheet in Google docs. You'll be on your way to tweaking your own probabilities that are suited to your campaign.

Whew. This brings us finally to the matter of


Much has already been said about this on the internets, so I won't belabor the topic like Leomund might (lamentably).

That was bad, Anthony.

I know. *hangs head*

All I will say is that sometimes, for very powerful items like the Ruby Gauntlet in The Mortuary Temple of Esma, I will provide a specific method and cost for recharging. But for most standard items, I require the Expendable Spell Requirement (Enchant Item/ Major Creation/ Commune/ Commune with Nature) to be cast upon the item. That's it. Nothing else. Enchant Item, therefore, will restore 1 charge to a rod, wand or staff. Commune will do the same for a clerical item.

I like this because it is simple yet also difficult to cast very many Enchant Item spells per day. Recall that level 5 and 6 spells require a full 8 hours of rest (plus the 1.5 hours of memorization if you are a stickler: note the additional quarter hour per spell level on p40 DMG that most DMs ignore.) Therefore, if more than a few charges are desired, a week a month or more might be needed to get the job done.

Such time sinks, I find, are of critical importance because if YOU care about them, so too will your players. They will hear you tell them about the changing seasons, the threat of an early snow or looming conflict between kingdoms. They will be surprised the first time you wish their character a happy birthday on the day of the month that their sheet claims they were born. Then, when you check the age categories (DMG p13) and apply any applicable adjustments they will begin to understand. Keeping a calendar is essential, just as Gary states on p37 DMG (read his reasons----no really: read his reasons). High-level characters should be wrapped up, at least occasionally, in time-critical pursuits against adversaries that do not pause their machinations while the PCs fabricate items or recharge wands.

These are the tools you should be using (with wisdom) to balance when and how often spell casters catch a break to fabricate magical resources.

Ahead: Part 3, where I'll conclude this discussion with magical languages and research, both for new and existing spells.

Until then, peace, Happy October

and happy gaming.

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