Skip to content

Welcome to, home of Yore

While I was comparing dungeon treasure stocking in B/X D&D and Labyrinth Lord, I noticed something in OD&D that surprised me: The way OD&D handles wandering monsters is delightfully unforgiving.

At a glance, B/X looked pretty different in this regard, so I thought I’d compare the two. Let’s just look at level 1 in both systems, and let’s assume the party is composed of level 1 PCs.

I’ll also assume that monsters with X+Y HD, like hobgoblins (1+1/2 in OD&D, 1+1 in B/X) count as 2 HD monsters. (This assumption is borne out by both systems, which list hobgoblins on their respective level 2 tables.)

Das tables

Here’s the wandering monster matrix from OD&D‘s Book III:

In B/X each dungeon level just has its own table, which includes a mix of monster HD values. Here’s the analogous table from the B/X Basic Set:

OD&D wandering monsters

In OD&D, a party exploring level 1 of the dungeon can encounter wandering monsters with a range of HD values.

The Monster Level tables roughly map 1:1 to HD, but not universally. For example, there’s a 5 HD monster, the ochre jelly, on the level 3 monster table. There are also monsters with suggested values, but no actual entries; giant animals fall into this category.[1]

But for our purposes, “roughly” is good enough. With that in mind, the chances of bumping into different levels — hit dice, more or less — of monsters look like this:

  • Monster Level 1 list, mainly 1 HD or lower: 33.33%
  • Monster Level 2 list, mainly 2 HD: 33.33%
  • Monster Level 3 list, mainly 3 HD: 16.67%
  • Monster Level 4 list, mainly 4 HD: 16.67%

One-third of the time, you’ll meet monsters whose HD match your level. Another third of the time, they’ll be 1 HD higher than you. The remaining third of your encounters will be with monsters 2 HD or 3 HD higher than you.

And that level 4 monster table is going to wreck your shit: wraiths, ogres, lycanthropes — if you’re not cautious and willing to run, be prepared to die instead.

B/X wandering monsters

In B/X, things are a bit different:

  • 1 HD or lower: 70%
  • 2 HD: 25%
  • 3 HD: 5%

The chance of encountering a 2 HD monster is roughly the same (25% vs. OD&D’s 33.33%), but what’s missing? Except for one 3 HD critter (the giant gecko), what’s missing is 3 HD and 4 HD monsters — which are encountered fully one-third of the time in OD&D!

The dungeon of B/X, at least on level 1, is a much tamer place than its OD&D counterpart. Wandering monsters still spell trouble, but not nearly as much trouble.

But wait, there’s more

You know what else changed between 1974 and 1981?[2] How often you check for wandering monsters. (The chance of an encounter, 1 in 6, is the same.)

In OD&D, it’s every turn. In B/X, it’s every two turns.

So not only is the B/X party unlikely to meet a 3 HD monster (5% chance) and guaranteed not to bump into any 4 HD monsters, they’re also going to have half as many random encounters overall. These are completely different dungeons.

Time is a resource in old-school D&D dungeon crawls in large part because of wandering monster checks, but OD&D really squeezes the ol’ temporal vice in this regard. If you don’t get in, grab some loot, and get out pretty quick, you’re playing with fire.

I’ve never played OD&D, but my interest in it has been growing over the past couple of years. This difference clinches it, though: I need to play some OD&D! I want to see this style of dungeon in action, rather than just in percentages.

A wild aside appears!

As an aside, while I’m normally a print guy and the photos I use in posts reflect that preference, I went with screenshots from my PDF copies this time around. This is partly because my OD&D set is in storage, but it’s also because I’ve been working from the PDFs a lot lately.

While I prefer the old covers, the layout and clarity of the OD&D PDFs is fantastic. The quality of the B/X PDFs is also high. Both have been a good investment, especially when I need to search for things while comparing editions.

[1] And then there’s Supplement I: Greyhawk, which removes the “optionally usable “Martian” animals such as Apts, Banths, Thoats, etc.” and adds new monsters to every list, making the picture fuzzier still. I’m sticking with “good enough.”

[2] Yes, I’m leaving out the Holmes Basic set, but only because my copy is in storage and I don’t have it in PDF. I’d love to see whether Holmes looks more like OD&D or B/X in this regard.

Tags: , , , , , , , , , , ,