Distributing Magic Items

The first step it to identify some 475 magic items that appear in the DMG, which is more than enough for my campaign. I've never felt much need to create more than a basic few items of my own, simple stuff, refilling jugs, flasks that provide healing salves, that sort of thing. But those can be left off the table for now and we can just use what's there in front of us. This collection of items appears as a list from pages 121 to 125 of the DMG, with a lot of description afterwards, most of it inadequate to the purpose.

The next step is to identify all the "sub-types" for those listed. For example, from the list shown, we have "dragon control" potion, but not which dragon is controlled, just as we don't know which giant is controlled or which giant's strength is obtained from the giant strength potion. These sub-types are determined by an additional roll that is made in the description of the potion: for example, the dragon control potion type is determined by a d20 roll found on p.125.

The reason this matters is because what's wanted is a likelihood ratio for all items as if they they were listed together in one table. To determine at the start whether to roll on the "potions" table or the "scrolls" table, and so on, there's an initial table at the top of page 121 that one rolls on first. To get the result of a white dragon potion, one has to roll first on that top table to determine a "potion," then on the potions table to get a "dragon control potion" as the result, then that d20 table to get "white dragon control potion." That's three tables. The total chance of getting that specific potion is therefore 0.2 x 0.02 x 0.1, which equals 0.0004. What's wanted is that universal number for every magic item, so that they can all be compared with each other, dispensing with tables that need us to roll on tables that in turn need us to roll on another table.

The system is fine. But what's wanted to is to create a new set of tables, from scratch, and not use that are pre-existing... while at the same time not actually changing the chance of each item in and of itself occurring as something the players can find.

Why accept the DMG's numbers? Because I've play-tested them for 47 years and those averages may be close to the best organisation of any part of original D&D. The only real problem is that they offer a chance of getting an incredibly powerful item when rolling for things that are much more common. That's not desirable. Not at all. What we want can be found on this page of my wiki.

The concept for determining a randomly given magic item is essentially this. First, we build a separate but easy to make table for the monster being plundered:

This is the troglodyte treasure, as discussed on this post, discarding the "treasure type A" moniker completely by merely designating the amount of treasure per individual, the only number that actually matters. From the above, if you kill ONE troglydyte in his personal lair, where he's just been hanging around a bunch of time, his wealth will equal 65 c.p., 137 s.p., 326 g.p., less than one gem and therefore none, less than one jewellery and therefore none, less than 100 magic item experience (the bare minimum needed) and therefore none. This total treasure compares rather fairly with how much a 2nd level fighter player character tends to have from adventuring, so why should the trog be any different?

Of course this can be viewed as an average. The single trog may have more, or it may have less... and logically, if this is what the trog keeps as wealth while not adventuring with others, this wealth may be secretly buried in a forest (in a "lair" some 8 inches cubed that consists of a hole, a bag and a large rock on top) where its not likely to be found. That's not the point. What matters is that we have a rational total, perhaps balanced by a die roll, that assures to things: a trog definitely has something, and it isn't the ridiculous 3-18 c.p. that orcs in the original game are assumed to carry around, for purposes that are never explained, since there are no stores to spend copper pieces at where the orcs are, and in game you can't buy much more than a chicken with that kind of scratch.

What matters is not what "one trog" carries regardless — because as a DM, you're never going to throw one trog at the party anyway. You know that five first levels are going to waste the trog forthwith, so logically the trog knows that too... and knows that there is safety in numbers. A lone trog is only "lone" for one reason: it's lost where the rest of its kin are.

The Magic Item Distribution page on the wiki, linked above, includes the following line: "With 22.3 x.p. per troglodyte, the total is 691, the fraction ignored. As such, one roll would be made on Table I and one upon Table III." Table I is sketched out on the page, broken into "Common Magic Items" with a sub-table for items so unlikely that they don't fit easily into the d100 format. The Rod of Absorption, with 1 charge, for example, has a 1 in 10,000 chance of being rolled randomly. That is also the likelihood of three other rods, one staff and two different wands. The reduced likelihood deserves an explanation.

Table I accounts for magic items with 100 to 200 x.p. value as rated by the DMG. Rods have 50 charges in them and the DMG states that a fully charged rod of absorption is worth 7,500 x.p. That makes each charge worth 150... so, a rod with 1 charge fits into the Table I range.

However, the base chance for rolling a rod of absorption from all possible magic items is 0.5 (the rods, staves and wands table) x 0.03 (1-3 of one hundred of the table itself). This equals a chance of 0.0015;
but importantly, a 1 charge rod has only a 1 in 50 chance of being found among all the rods of that kind out there (by the logic I'm using), so that chance is reduced by another 0.02 to a final chance of 0.00006. Considerably less of a chance than finding a healing potion.

Here's my workup of Table I in excel (please just ignore the shading):

Everything that didn't produce enough chance to push the die roll another point in the main table was shoved into the rare item subtable, which is rolled on if 98-00 is rolled on the common table. The numbers all reflect how many charges at this table rank count against the total charges of that item: a wand of magic has 8 out of 100 possible charges, while the wand of metal & mineral detection has 13 out of 100 possible. Together, that's why these are more likely, along with the fact that the DMG makes them more likely overall.

At this point some wise ass raises a hand and says, "Hey, if the wand of illumination has 20 x.p. per charge, why can't the single troglodyte have an illumination wand with 1 charge? Huh? Why not?"

Because, totally arbitrarily, I'm setting a 100 x.p. minimum for magic. Point in fact, by the logic I've just explained, the 1 charge illumination wand would have a 0.000025 chance out of 1 (0.0025%) chance of existing at all. Thus out of 40,000 single troglodytes out there, one of them would have a single charge illumination wand. Yeah. I'm drawing the 100 x.p. line against this sort of nonsense, and pegging the table at 150 x.p. average for distribution purposes. You don't like it, you go ahead and do it your way.

I think this about covers it. I tried to manage the same process with determining the percentage of scrolls based on the scroll table in the DMG and, I must say, I'm not really satisfied that my judgment was sound there. I'm okay with the result... and at some point screwing around getting more accurate so that a number can be changed from 15 to either 14 or 16 just doesn't become worth the skull sweat. Like a bad accountant, I tend to think, "Well, I'm close... so fuck it."

See, it's the way Gygax conceived of scroll distribution on that table... which is really, really annoying. Go look at it.

That's about all. I still have to make table III (I have it in excel right now, but not laid out on the wiki) before Friday's game... unless, of course, the party all die or they fail to get the treasure. But I don't know they will, so I have to ready that table in case they succeed.

Are we all having fun?