D&D General The Rules Cyclopedia - Unlearning Dnd Preconceptions from a 3e player

[Weiley31]

There are several options to deal with this. One is to just use the B/X progression chart instead. Then what does the thief do after level 14? That's down to you.

Grim Reaper's masterpiece of RC errata (found here: Dungeons & Dragons Rules Cyclopedia Errata and Companion Document Download Page) also contains a suggestion. Allow the thief to attempt a skill at a level above current per dex bonus mod. (so a +2 dex bonus would mean a 3rd level thief could attempt to open locks as a 5th level thief). He also provides a complete homebrew rework for taste as well.

I've also heard a number of people suggest using the Specialist skill system, from Lamentation of the Flame Princess, instead of the percentages as apparently its more reliable, or something, and not super stretched out.

 

[Mannahnin]

I've also heard a number of people suggest using the Specialist skill system, from Lamentation of the Flame Princess, instead of the percentages as apparently its more reliable, or something, and not super stretched out.

The Specialist system from LotFP is pretty solid.

One of my very short list of house rules for B/X style D&D is just to have Thieves use the Hear Noise column for all their skills. Keeps it super simple and improves their chances.

I also interpret their skills generously when they work. Anyone lightly-armored and not carrying an encumbering amount of equipment can move quietly; a thief who makes their Move Silently check moves with ABSOLUTE NINJA-LIKE SILENCE.

 

[Voadam]

I am a fan conceptually of Necrotic Gnome's B/X Rogue where thieves get specific chooseable talents instead of percentage skills.

 

[Mannahnin]

I've been meaning to check that one out. Thanks for the reminder.

 

[transmission89]

I still recommend the Collins piece.

What is the Best Combat Algorithm?

Math, history, and design of old-school D&D.

deltasdnd.blogspot.com

Excerpt:

"...Now, obviously, those last few were for humorous illustrations only, and I assume not many people would want to use those systems. But what criteria can we use to choose the "best" possible system? Let's consider the following as guiding principles (and we'll back each of them up with results from experiments in cognitive psychology as we proceed):

(1) Additions are easier than subtractions. Although mathematically equivalent (and using fundamentally the same operation in digital computing systems), most people find subtraction significantly harder than addition. For example, see the paper by MacIntyre, University of Edinburgh, 2004, p. 2: "Addition tasks are clearly completed in a much more confident manner than the subtraction items, with over 80% of the study group with at most one error on the items. Subtraction items appear to have presented a much bigger challenge to the pupils, with over 50% having 3 or more of those questions wrong."

(2) Round numbers are easier to compare than odd numbers. In other words, when comparing which of two numbers is larger (the final, required step in any "to hit" algorithm) it will be easier if the second number is "20" than, say "27". This follows from the psychological finding that it's faster to compare single digits that are farther apart; see Sousa, How the Brain Learns Mathematics, p. 21: "When two digits were far apart in values, such as 2 and 9, the adults responded quickly, and almost without error. But when the digits were closer in value, such as 5 and 6, the response time increased significantly, and the error rate rose dramatically..." In our case, setting the second digit to zero would maximize the opportunity for a large (and thus easy-to-discern) difference between the numbers.

(3) Small numbers are easier to compare than large numbers. This has also been borne out by a host of psychological experiments over the last several decades. Again from Sousa, p. 22: "The speed with which we compare two numbers depends not just on the distance between them but on their size as well. It takes far longer to decide that 9 is larger than 8 than to decide that 2 is larger than 1. For numbers of equal distance apart, larger numbers are more difficult to compare than smaller ones." Again, this is true for human computers only, not digital ones (ironically, the digital processor "compare" operation is really just an application of the same "subtract" circuitry).

Okay, so let's think about applying these principles to find the cognitively-justified best tabletop resolution algorithm. Applying principle #3 means that we'd generally prefer dealing with smaller numbers rather than larger. Before considering anything else, it's clear that it will be hardest for people to mentally operate in a d% percentile system, easier in a d20-scaled system, and easier still on a d6-scaled system. We should pick the easiest of these that gives the fidelity necessary to our simulation, and the d20-scale does seem like a nice medium..."

I’m aware of that article and read it previously. It’s an interesting read and provides food for thought. A couple of critiques is that the Macini paper linked there seems to be all Swedish, but the images in the article seem to be referring to casinos.

Here you are dealing with a larger number range than that presented with the 10 to - 10 range.

secondly, the algorithm used for THAC0 in the article compares to 20 as an operation, not a method I favour.

To be clear on my position: I am not arguing THAC0 is superior. I recognise ascending armour class (aac) is superior in that it’s easier to relate a concept of bigger is better. I happily use aac in modern games I play.

I do however reject the idea that THAC0 (in particular, basic subtraction) is complex enough to have an appreciable negative impact on the play of OSR games. With the number ranges offered and the maths proficiency needed to access a game of d&d (either ascending or descending) the difference in calculation time is milliseconds at most.

For me it is not worth the time to either calculate on the fly or pre convert ACs and hit bonuses on old modules. That is DEFINITIVELY, measurable time lost doing that (even though the sums are simple, there are at least two mathematical operations I have to make per monster rather than just one THAC0 role) versus a player taking a bit longer.

In fact, with the older systems, what gets lost in discussions of THAC0, is that with the low number range and (mostly clear cap), a lot of the time, you don’t even need to make a calculation at all. You can just clock the die roll based off the armour the bandit is wearing. Even if they are heavily armoured, if you roll 2 or 3 points below your THAC0, chances are you’ve hit them. The same cannot be said so much for aac systems (with potentially more dex modifiers and a more vague AC cap). Of course, there are exceptions to each of these, but the general principle holds.

That is why I happily use THAC0 in my OSR games and don’t think it deserves the denigration it gets in online discourse. As always, of course, ymmv and do whatever works for your table.

 

[Imaculata]

Everyone hates THAC0, which always struck me as odd, because it was just a matter of "Your THAC0, minus the enemy's AC, equals the number (or higher) that you need to roll to hit them on a d20." It was certainly easier than pages of combat matrices like in AD&D 1E.

Two problems with that: You would needed to be told what the AC of each enemy is, and 2E had negative AC values. It meant a confusing bit of math every single time.

I cannot overstate how much better 3E's rules were, of simply rolling an attack, and it having to be equal or higher than the AC of your enemy. It made so much more sense.

 

[transmission89]

Two problems with that: You would needed to be told what the AC of each enemy is, and 2E had negative AC values. It meant a confusing bit of math every single time.

I cannot overstate how much better 3E's rules were, of simply rolling an attack, and it having to be equal or higher than the AC of your enemy. It made so much more sense.

Thank you for proving my point in the post right below.
Except again, you didn’t need to know the enemy ac. Ac hit = THACO -(roll + mods). You hit any ac equal or lower, the same as 3e but inverted.

Again, it is not “a confusing bit of maths”. It is simple subtraction.

As for confusing maths, I can’t believe the idea that the same people that find basic subtraction “immensely difficult” are the same that can keep track of the numerous floating modifiers (based on conditions in the game state) which complicate the vaunted “easy maths of 3e” beyond just a simple addition.

Again, I get additive maths in general is the preferred way of doing things. I get that it makes more sense. But can we stop propagating this myth that primary level Subtraction maths is “confusing maths”.

 

[Imaculata]

Again, I get additive maths in general is the preferred way of doing things. I get that it makes more sense. But can we stop propagating this myth that primary level Subtraction maths is “confusing maths”.

It is not a myth. From personal play experience (and I'm sure many other 2E players have a similar experience), every-single-time an attack roll needed to be made, it tripped people up. It never stopped being confusing, no matter how often we had to make the same rolls. And the negative armor values added to this confusion. It just wasn't a pleasant rule to work with.

I'd rather add dozens of modifiers to my d20 roll, than ever have to work with Thac0 and negative armor class ever again. It really was terrible. And so were the countless saves. There was a good reason we moved on to 3E.

 

[transmission89]

It is not a myth. From personal play experience (and I'm sure many other 2E players have a similar experience), every-single-time an attack roll needed to be made, it tripped people up. It never stopped being confusing, no matter how often we had to make the same rolls. And the negative armor values added to this confusion. It just wasn't a pleasant rule to work with.

I'd rather add dozens of modifiers to my d20 roll, than ever have to work with Thac0 and negative armor class ever again. It really was terrible. And so were the countless saves. There was a good reason we moved on to 3E.

Quick: what’s 17-12?
17 - 10?
17 - 8?
17 - 19?

congratulations, you just used THAC0 to work out the armour hit 4 times in quick succession. That’s all there is to it.

 

[Imaculata]

congratulations, you just used THAC0 to work out the armour hit 4 times in quick succession. That’s all there is to it.

That is irrelevant. What matters is how it plays. And it plays awful! Every single time it trips people up! Yes, in principle it should be simple. But it is just down right unpleasant and illogical to work with. It goes against the way many of our brains are wired. They changed it with good reason.