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When Do Smarter Wizards Deserve More XP?

posted Saturday, May 29th 2010 by Jonathan Drain
None of the Above

As I said previously on the odds of each result when rolling 3d6, D&D was a lot more lethal back in 1981. Your character can start with as little as one hit point.

Another odd quirk of the Basic D&D rules, which you can see in Labyrinth Lord‘s rules (free PDF download here), is that characters with high ability scores gained bonus XP. Since you rolled ability scores before choosing character class, this encouraged players to pick a stat-appropriate class and to alue these rare and powerful characters.

But how rare are they really?

Early D&D and its modern clone Labyrinth Lord give bonuses or penalties to actions based on ability scores, much like third edition D&D’s ability score modifiers. However, statistical analysis shows that bonuses are much rarer than in third edition. The “4d6 drop lowest” ability score generation method in D&D third edition gives a 61.65% chance for each ability score to have some bonus, and only a 17.51% chance of a penalty.

In Basic D&D and Labyrinth Lord when using 3d6, about 48% of ability scores will occur in the range 9-12, which in Basic D&D and LL is a +0 modifier. There’s a 26% chance of a bonus and 26% chance of a penalty, usually only +1 or -1.

Above-average ability scores also grant a bonus to XP if you choose a class for which that ability score is a prime requisite: 13-15 grants +5%, and 16+ grants +10%. Since class can be chosen based on ability scores, only one high score is necessary to gain the bonus.

Around 25% of characters qualify for the 10% XP bonus, and 83.48% gain some bonus XP, if there are classes available for all ability scores. Since the Labyrinth Lord core rules have no classes for which Constitution or Charisma are prime requisites, only 17.272% of characters will gain the 10% XP bonus and 69.893% will gain any XP bonus.

Here is the full list for Basic D&D / Labyrinth Lord. The Modifier listed applies to various uses of some ability scores, but not all. The percentage listed is the chance of this result on one roll of 3d6.

Score  Mod.    XP  Percentage
-----  ----  ----  ----------
3      (-3)  -10%      0.463%
4-5    (-2)  -10%      4.167%
6-8    (-1)   -5%     21.296%
9-12   ( 0)   +0%     48.148%
13-15  (+1)   +5%     21.296%
16-17  (+2)  +10%      4.167%
18     (+3)  +10%      0.463%

World Building 101 – Creating Cultures

posted Thursday, May 27th 2010 by Brandan Landgraff
Dungeon Mastering Advice

Last week we discussed real world cultures as a shortcut for generating your own full-fledged cultures for use in your campaigns. This week we will examine some things to consider when creating your own cultures for your campaign setting.

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What Are The Odds When Rolling 3d6?

posted Tuesday, May 25th 2010 by Jonathan Drain
None of the Above

You kids today have it easy. Back in the early days of D&D you rolled 3d6 for ability scores, placed in the order you rolled them. No “4d6 drop lowest” or “arrange as desired” – if you roll a 3 for Strength, your character has 3 Strength. Looks like you aren’t playing a fighter this time.

Labyrinth Lord (free download here) is a Basic D&D retro-clone that still uses 3d6 for ability score generation. By third edition or fourth edition D&D standards, LL is quite deadly: poison kills you outright, and dragon’s breath weapons deal their current hit points in damage.

But what are the odds of rolling each ability score on 3d6? I wrote up a quick python script like my 4d6 drop lowest calculator from 2006.

Firstly, the average roll on 3d6 is 10.5, compared to 12.244 on 4d6 drop lowest. The “human average” +0 modifier in third edition D&D comes from this result.

The odds of rolling an 18 are an unlikely 0.463%, or one in 216. The odds of rolling at least one 18 are 2.746%. In both cases this is about 3.5 times harder than third edition D&D’s 4d6 drop lowest. It’s around 20 times harder to get an 18 in a particular ability score, since early D&D required that you assign the ability scores in the order they’re rolled.

Here’s the full chart of results of 3d6:

Score   Freq   Percentage
-----   ----   ----------
3          1       0.463%
4          3       1.389%
5          6       2.778%
6         10       4.630%
7         15       6.944%
8         21       9.722%
9         25      11.574%
10        27      12.500%
11        27      12.500%
12        25      11.574%
13        21       9.722%
14        15       6.944%
15        10       4.630%
16         6       2.778%
17         3       1.389%
18         1       0.463%

The Difference Between Board Games and RPGs

posted Sunday, May 23rd 2010 by Jonathan Drain
None of the Above

Justin Alexander hits the nail on the head:

The reason we look for verisimilitude in the rules of a roleplaying game and not in the rules of Monopoly is because we don’t play roleplaying games as if they were a round of Monopoly.


Personally, I look at the rules of a roleplaying game as the interface between me and the game world. I want those rules to be fun and interesting, but I also want them to be transparent: My primary interest is interacting with the game world. If I wanted to interact with the rules of a game, I’d play a boardgame like Monopoly or Arkham Horror.

So if the rules in a roleplaying game get in the way — either due to a lack of verisimilitude; or because they’re boring; or dissociated; or too complicated — then I’m going to be unhappy with those rules.

World Building 101: Real World Cultures in Fantasy Games?

posted Thursday, May 20th 2010 by Brandan Landgraff
Dungeon Mastering Advice

Any long-term reader of fantasy fiction or player of fantasy games will have at one point or another encountered a setting that uses real-world cultural analogues. In these settings, nations or people are often described in such a way that their cultures are clearly inspired by or directly lifted from an existing real-world culture, living or dead.

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D&D Rube Goldberg Dice Rolling Machine

posted Monday, May 17th 2010 by Jonathan Drain
None of the Above

World Building 101: How Long Should Your Campaign Be?

posted Thursday, May 13th 2010 by Brandan Landgraff
Dungeon Mastering Advice

Most long-time RPG players have heard stories of long-running campaigns that last for years or more, with the characters growing from first-level scrubs to godlike proportions, or even passing on their powers to their heirs and continuing to adventure for generations in the same world. It is, however, not all that common to find a game that lasts that long, for a variety of reasons.

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World Building 101 – Avoiding “Filler”

posted Thursday, May 6th 2010 by Brandan Landgraff
Dungeon Mastering Advice

When telling any kind of story it is important to consider the medium for which you are writing and tailor your techniques to fit. The general structure of a story–beginning, middle, end–may remain in roughly the same shape, but the methodology of communicating the details is necessarily different from format to format. One would use a different style if writing for television than one would for a novel, or for a serialized comic book compared to a single motion picture. The same holds true of gaming–as a DM you need to consider carefully what techniques you will apply to tell the story of your campaign. How you decide to do so will impact the emphasis you place on other aspects of world building and campaign structure.

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