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Playing D&D With Six-Sided Dice Copyright© 2013 J.D. Neal All Rights Reserved Note: DUNGEONS & DRAGONS, D&D and all other Wizards of the Coast product names, and their respective logos, are trademarks of Wizards of the Coast (WOTC) in the U.S.A. and other countries. This document makes no claim to any form of relationship to WOTC or its products. More than one person has posited the idea of playing D&D with six-sided dice, and some people even do it. Most discussions I have seen involve older, simpler versions of the game, but after looking at newer versions I saw no reason not to try it with them, too. Using the standard dice (d20, d8, etc.) is very simple and straightforward. If you have them and like them, use them. This discussion is for gamers who want to explore the use of d6s. Perhaps they want to throw a couple of dice in a bag and play D&D on the move, without a lot of dice, rules, etc. Of course, some people will spout all sorts of "You can't do that! D&D was made for the d20!" comments. Never mind that D&D was originally published as a supplement to the Chainmail combat rules (which was based entirely on d6s) and the use of the d20 and other dice was an alternate choice. Let alone dice and numbers are just tools of the game. People nay-saying the idea are more interested in numbers than adventuring; at one time numbers were merely a means to the end (a way of playing the game). Anyone with experience has seen them change, not to improve the game but rather to fit the specific interests of whoever was allowed to design the game. There has never been a single variant of D&D that was like all others. Some were close, but D&D has seen many forms from the very beginning. And each featured a number set intended to express a style of play. The "six-sided dice" number set expresses the "simple and easy" style of play, reducing numerology in favor of adventure. This is intended for the experience gamer, not a novice who struggles over basic terminology. Damage When it comes to quantities, the goal is usually to mimic the average of the original or create a scale like the original. Older games were often based greatly on d6s for damage, so conversions aren't quiet a tedious. The earliest version of D&D didn't even use variable damage rolls. All attacks did 1d6 damage, including those by monsters, though certain monsters were given extra dice to make them more deadly. And all creatures made only one attack. Simplicity was the name of the game. Eventually variable damage and different numbers of attacks was introduced. The intent of variable damage is to create a scale: a d4 does less damage than a d6 which does less than a d8, and so on. The substitute for this is simple. d4 d6-1 or d6 reroll 5 or 6 or quasi-d4 d6 d6 d8 d6+1 d10 d6+2 or d6+d3 d12 2d6 or d6 x 2 d14 2d6+1 d16 2d6+2 or 2d6+d3 d18 3d6 Repeat the pattern as needed. Note that the above does not give the same high and low numbers but does give much the same average (except rolling 1d6-1 for a d4). Mathematically speaking: divide the maximum point value by 6 to find how many dice to roll: if there is a remainder of 1 or 2, the roll is "+1"; if it is 3 or 4 the roll is either "+2" or "+d3"; if it is 5, add another dice. Thus, 4-32 damage becomes 5d6+1; 6-34 becomes 5d6+2 or 5d6+d3. Hit Points Some games use set hit points. The approach to random hit points can vary depending on whether the user prefers averages, something close, or to simply base them on d6 with changes for the original die type. Examples: Hit Die Solutions Type Average d6 base d4 a d4 substitute d6-1 d6 as-is as-is d8 d6+1 (average 4.5) d6+2 (3 - 8) d10 d6+2 or d6+d3 (average 5.5) d6+4 d12 a d12 substitute d6 x 2, 2d6, d6+6 Probabilities Probabilities are a concern for succeed or fail die rolls: saving throws, to-hit rolls, skill rolls, etc. And random table picks. While some people try to convert various games to 3d6, 2d6 or d12 using math and comparing percentages, the author prefers to reformulate the game. There is no reason to take what is basically a simple game and add complexity: keep the underpinnings simple and let the dice speak for themselves and have their own effect on the game. Many people are used to thinking about probabilities in terms of decimals. Decimals are handy, but what some people forget or never think of is that a decimal is more properly the "decimal representation of a fraction." 1

Playing D&D With Six-Sided Dice

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Playing D&D With Six-Sided DiceCopyright© 2013 J.D. NealAll Rights Reserved

Note: DUNGEONS & DRAGONS, D&D and all other Wizards of the Coast product names, and their respective logos, are trademarks of Wizards of the Coast (WOTC) in the U.S.A. and other countries. This document makes no claim to any form of relationship to WOTC or its products.

More than one person has posited the idea of playing D&D with six-sided dice, and some people even do it. Most discussions I have seen involve older, simpler versions of the game, but after looking at newer versions I saw no reason not to try it with them, too.

Using the standard dice (d20, d8, etc.) is very simple and straightforward. If you have them and like them, use them. This discussion is for gamers who want to explore the use of d6s. Perhaps they want to throw a couple of dice in a bag and play D&D on the move, without a lot of dice, rules, etc.

Of course, some people will spout all sorts of "You can't do that! D&D was made for the d20!" comments. Never mind that D&D was originally published as a supplement to the Chainmail combat rules (which was based entirely on d6s) and the use of the d20 and other dice was an alternate choice.

Let alone dice and numbers are just tools of the game. People nay-saying the idea are more interested in numbers than adventuring; at one time numbers were merely a means to the end (a way of playing the game). Anyone with experience has seen them change, not to improve the game but rather to fit the specific interests of whoever was allowed to design the game.

There has never been a single variant of D&D that was like all others. Some were close, but D&D has seen many forms from the very beginning. And each featured a number set intended to express a style of play. The "six-sided dice" number set expresses the "simple and easy" style of play, reducing numerology in favor of adventure.

This is intended for the experience gamer, not a novice who struggles over basic terminology.

DamageWhen it comes to quantities, the goal is usually to mimic

the average of the original or create a scale like the original. Older games were often based greatly on d6s for damage, so conversions aren't quiet a tedious.

The earliest version of D&D didn't even use variable damage rolls. All attacks did 1d6 damage, including those by monsters, though certain monsters were given extra dice to make them more deadly. And all creatures made only one attack. Simplicity was the name of the game.

Eventually variable damage and different numbers of attacks was introduced.

The intent of variable damage is to create a scale: a d4 does less damage than a d6 which does less than a d8, and so on. The substitute for this is simple.

d4 d6-1 or d6 reroll 5 or 6 or quasi-d4d6 d6d8 d6+1d10 d6+2 or d6+d3d12 2d6 or d6 x 2d14 2d6+1d16 2d6+2 or 2d6+d3d18 3d6

Repeat the pattern as needed.Note that the above does not give the same high and

low numbers but does give much the same average (except rolling 1d6-1 for a d4).

Mathematically speaking: divide the maximum point value by 6 to find how many dice to roll: if there is a remainder of 1 or 2, the roll is "+1"; if it is 3 or 4 the roll is either "+2" or "+d3"; if it is 5, add another dice.

Thus, 4-32 damage becomes 5d6+1; 6-34 becomes 5d6+2 or 5d6+d3.

Hit PointsSome games use set hit points. The approach to random

hit points can vary depending on whether the user prefers averages, something close, or to simply base them on d6 with changes for the original die type. Examples:

Hit Die SolutionsType Average d6 based4 a d4 substitute d6-1d6 as-is as-isd8 d6+1 (average 4.5) d6+2 (3 - 8)d10 d6+2 or d6+d3 (average 5.5) d6+4d12 a d12 substitute d6 x 2, 2d6, d6+6

ProbabilitiesProbabilities are a concern for succeed or fail die rolls:

saving throws, to-hit rolls, skill rolls, etc. And random table picks.

While some people try to convert various games to 3d6, 2d6 or d12 using math and comparing percentages, the author prefers to reformulate the game. There is no reason to take what is basically a simple game and add complexity: keep the underpinnings simple and let the dice speak for themselves and have their own effect on the game.

Many people are used to thinking about probabilities in terms of decimals. Decimals are handy, but what some people forget or never think of is that a decimal is more properly the "decimal representation of a fraction."

1

The chance of any number appearing on a common d20 is 1/20 or 5%. The chance of a 12 occurring when making a standard 2d6 roll is 1/36, which is converted to 2.7 (repeating). Indeed, each combination (number) on a 2d6 roll is some fraction of 36. The chance of a 1 or 2 occurring on a d6 is 2/6 or 1/3, which gives a repeating remainder (or .333 repeating).

If you try to do various conversions and get bogged down, consider working with the true fraction that a probability is represented by.

Analyzing Die Rolls: Anecdotes vs. RealityDice are random number generators. How they are

made and rolled can affect outcomes. Plus they are random: randomness itself means they should not be predictable, which means one person may very well get the same numbers a lot while another may get a wide mix of numbers - just because they are unpredictable.

Thus, die rolls cannot be analyzed by anecdotes like, "I wrote down all my die rolls and they weren't any different than a d12." or "I actually get mostly 2s and 12s." Such things happen because of randomness, the dice being used, rolling techniques, lies, or ignorance.

The concepts involved have to be analyzed from a viewpoint of what will generally happen to a large population over a long period of time when using honestly random die rolls.

Making Standard Die Rolls Using Only d6sOne of the simplest methods that requires no conversion

of the game itself (just conversion of die rolls) is to make d10 and other die rolls using d6s.

A d6 is of course the d6.A d12 is made by rolling a d6 and reading it as-is; roll

a second die and interpreting it as "add 6" if the result is an even number (odds mean "add nothing" or "add 0"). Or you can use 1 to 3 as "add 0" and 5 to 6 as "add 6" - there are numerous ways to interpret the dice to get the same thing.

A d10 roll can be made by rolling two dice. One, (the base die) is rerolled if a 6 occurs but it is otherwise read as-is for a base of 1 to 5. If the other (a control die or adder) is even then add 5 to the base die (if it is odd then don't add anything). The result is a number from 1 to 10.

With a second control die that is read as "add 10" if the result is even, a d20 roll can be made.

A d4 is made by rolling a d6 and re-rolling 5 or 6. For quantities, the 5 can be counted as 2 and 6 as 3, which gives the same average as a standard d4. A d8 is made by adding a control die, and reading evens on it as "add 4".

And there you have it: a die roll for a d4, d6, d8, d10, d12, and d20.

d4 Roll d6, reroll 5 or 6, or make a quasi-d4d5 Roll a d6, reroll 6.d6 A d6d8 A d4 roll with an adder die: evens = add 4.d10 Roll a d5 and an adder die (add 5 if the adder is

even).d12 A d6 and adder die (add 6 if he adder is even)

d20 A d10 roll and an adder die: add 10 if even

Rather than adder die, coins or poker chips can be used with "0" on one side and the added number on the other (4, 5, 6, or 10).

Below is an example of a "quasi-d4", one way of using a d4 to create a 1 - 4 roll with the same average as a d4 for quantities. With individual die rolls, 2 and 3 are favored, but in the long run (barring any bias on the die roller's part or random flukes) the total quantity will be much the same as a d4 was rolled.

d4 Weighted Quasi-d4# Frequency Value # Frequency Value1 25.0% 0.3 1 16.7% 0.22 25.0% 0.5 2 16.7% 0.33 25.0% 0.8 3 16.7% 0.54 25.0% 1.0 4 16.7% 0.7

2 16.7% 0.33 16.7% 0.5

Average: 2.5 15 Average: 2.52.5

D&D With 3d6Since ability scores are typically based on the 3 to 18

number range and often determined by rolling 3d6, some people consider using 3d6 instead of a d20 roll. Thus is not a new idea. Games such as GURPS, Dragon Age, The Fantasy Trip (Melee, Wizard, etc.), and the SwordQuest game book series use a 3d6 as the standard resolution die roll. There are various tutorials that use 3d6: J. Eric Holmes offered one, Ian Livingston's Dicing With Dragons included one and then there was the Smoke Dragon fast play introduction for Dungeons & Dragons circa 1999 or 2000.

Rolling 3d6 favors the middle number and slights the end numbers quiet a bit. Some people may like that: others may not. Those who do not can always make a d18 die roll instead, which involves only two dice, as explained later.

3d6 ProbabilitiesCumulative %

# Each % Asc % Desc3 1/216 0.5% 0.5% 100.0%4 3/216 1.4% 1.9% 99.5%5 6/216 2.8% 4.6% 98.1%6 10/216 4.6% 9.3% 95.4%7 15/216 6.9% 16.2% 90.7%8 21/216 9.7% 25.9% 83.8%9 25/216 11.6% 37.5% 74.1%

10 27/216 12.5% 50.0% 62.5%11 27/216 12.5% 62.5% 50.0%12 25/216 11.6% 74.1% 37.5%13 21/216 9.7% 83.8% 25.9%14 15/216 6.9% 90.7% 16.2%15 10/216 4.6% 95.4% 9.3%16 6/216 2.8% 98.1% 4.6%17 3/216 1.4% 99.5% 1.9%18 1/216 0.5% 100.0% 0.5%

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A 3d6 roll changes the flavor of the game. With a d20, everything is flat and a 20 will occur just as often as a 1 or any other number, instilling a lot of randomness to play and reducing the effect of bonuses and penalties.

With 3d6, the game becomes more predictable: indeed, die rolls will greatly favor 9, 10, 11, or 12. Some people like this because, in the end, randomness does tend to create chaos. Yes, the characters might win a fight by rolling great on a d20; and they may also loose it by rolling poorly.

Most die rolls will be average, and the strongest side will tend to prevail by the law of averages. The differences in bonuses and penalties become more significant; the smaller modifiers of +1 or so can stack up and become more important by pushing the overall bonus higher. Note how (when modifiers are more level due to using a d20) it is possible for characters to function somewhat like each other if they manage a bonus in the same general area - such as one character with a +3 bonus to hitting due to high strength while another has a +6 bonus due to strength and perhaps a higher experience level. Using 3d6, though, the +6 bonus can be far more significant than a +3 bonus because, in the end, both characters will usually roll the same thing.

Critical failures and critical successes will become less common and have to be adjusted for the newer number ranges.

It becomes much tougher to make high saving throws or hit high armor classes; and a bit easier to make lower ones (high meaning "higher number needed to succeed"). Tough monsters become much tougher and weaker monsters loose some of their danger. Succeeding by random luck is not as easy; a referee used to more randomness from d20s has to be careful not to blithely throw tough monsters at the party as the monsters will be even tougher with 3d6.

You wind up with a different feel to play, one that some people enjoy.

Percentiles With 2d6The following table shows how to approximate some

percentiles using a 2d6 roll. This is based on number set theory: grouping numbers by a certain percent and then treating all numbers in said set as that percent. That is to say, there is a 55% chance that a 2d6 roll will be a 5 or 6 or 7 or 8: thus if 55% is the goal, success is indicated by getting a 5, 6, 7, or 8. Anything else is failure.

Note that there are many possible combinations to create the same basic thing; the following was tweaked to suit "higher = better" concepts and in some cases uses fewer exceptions than similar tables the author has seen. The users must define a specific set of numbers as the only allowed set for a result.

Number Rolled Percentage Actual Percentage11 5% 5.6%9 10% 11.0%8 15% 13.9%7, 12 20% 19.4%7, 10 25% 25.0%7, 8 30% 30.6%

7, 8, 11 35% 36.1%6, 8, 9 40% 38.9%6, 7, 8 45% 44.4%7, 8, 9, 10 50% 50.0%5, 6, 7, 8 55% 55.6%5, 6, 7, 8, 11 60% 61.1%5, 6, 7, 8, 9 65% 66.7%5, 6, 7, 8, 9, 11 70% 72.2%All except 5, 6 75% 75.0%All except 2, 7 80% 80.6%All except 2, 5 85% 86%All except 4 90% 92%All except 3 95% 94%All 100% 100%

d20 to 2d6While some people try to convert a d20 roll to 2d6 or

d12 using math and comparing percentages, the easiest way is to use basic ideas and reformulate the game. There is no way nor reason to slavishly try to replicate the numbers of a game; it is easier to recreate a game that plays much the same way as the original.

The average roll of a d20 is 10.5; often 1 to 10 is considered failure and 11 to 20 success. To-hit rolls, saving throws and such typically increase or decrease from the middle. The to-hit tables of older games often starts at 10 rather than 11, but since that applies to monsters and characters alike, it is not so important.

Rather than use 2d6, base a 2d6 game on a d12 roll. The average is 6 or 7: 1-6 is failure and 7 to 12 success.

As an example: in older games, using a d20 roll start at 10; leather armor often increases protection 2 points; chain mail 4 points; plate mail 6 points; etc. On a d12/2d6 roll, start with 6 and leather adds 1, chain mail 2, plate mail 3, etc. A shield adds 1.

Saving throws can be reworked much the same: in older games a fighter might start with 14, 16, and 18 - converted to a 2d6/d12 system that is close enough to 9, 10, and 11.

The intermediary numbers are lost (i.e. 13 and 14 both become 9), but the intent is to play a simpler game and such simplifications help reduce tracking picky numbers.

d20 to d18Using a d18 roll instead of a d20 gives the option of

not changing anything but the end point of 18 rather than 20. Those wanting a slight change might subtract 1 from the number needed for a d20 (counting 0 as 1) to bring it closer to the d18 center point of 9 and 10. Those wanting to develop their own play-alike game might simply start with the center points of 8 or 10 and adjust as explained above: i.e. leather armor adds 2 points protection, a shield 1, and so on.

Adder Dice and d6sAdder dice expand the versatility of the d6. Indeed,

the d18 roll can be used in place of a d20 and hence even many modern versions of D&D (let alone any d20 game) can be played in most part using just d6s with few changes.

Consider the following table. Mark a six-sided die as

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follows and roll it with a regular die (adding the two results) and you get a flat number range.

Used Remarked d6For Roll 1 2 3 4 5 6

d12 0 0 0 6 6 6d18 0 0 6 6 12 12d36 6 12 18 24 30 0

NOTE: The "d36" adder can be marked however you wish. The system shown makes it easy to roll a regular die and multiply by 6, counting the die face of "6" as "0" instead of 36.

There is no reason to stop there. Mark a third die as follows:

Used Remarked d6For Roll 1 2 3 4 5 6

d24 0 0 0 12 12 12d108 0 0 36 36 72 72d216 36 72 108 144 180 0

Roll (and add together) the d24 adder, the d12 adder and a normal six-sided die (d6) and the result is a number from 1 to 24. If you own a normal d12, you can roll the d12 adder with it for a total of 1 to 24.

Roll the d108 adder, d36 adder, and a normal d6 and the total will be a flat number from 1 to 108. This is clumsy, but it works.

This concept is not new: it was suggested in the some of the earliest role-playing games produced. It can be expanded to the use of other dice in infinite ways. Consider an 8-sided die interpreted as follows and added to yet another d8:

1 2 3 4 5 6 7 8d64 8 16 24 32 40 48 56 0

d66, d36 etcSome gamers use a "d66" roll, which is very similar to a

d100 roll using two ten-sided dice except it generates 36 numbers from 11 to 66. Two d6s are rolled (or one d6 is rolled twice) and one is read as the tens digit and the other as the ones digit.

d66 d36 Result d66 d36 Result d66 d36 Result11 1 31 13 51 2512 2 32 14 52 2613 3 33 15 53 2714 4 34 16 54 2815 5 35 17 55 2916 6 36 18 56 3021 7 41 19 61 3122 8 42 20 62 3223 9 43 21 63 3324 10 44 22 64 3425 11 45 23 65 3526 12 46 24 66 36

A d36 roll can be made using a d3 as the tens digit and creates the first 18 combinations of the d66 (11 to 36).

The concept can be used to make d666, d366, d336 rolls and so on.

Converting a d66 (and hence d36) roll to a d20 (rounding up) gives this.

d66 d36 raw % d20 raw d20 int11 1 2.8% .56 112 2 5.6% 1.11 113 3 8.3% 1.67 214 4 11.1% 2.22 215 5 13.9% 2.78 316 6 16.7% 3.33 321 7 19.4% 3.89 422 8 22.2% 4.44 423 9 25.0% 5.00 524 10 27.8% 5.56 625 11 30.6% 6.11 626 12 33.3% 6.67 731 13 36.1% 7.22 732 14 38.9% 7.78 833 15 41.7% 8.33 834 16 44.4% 8.89 935 17 47.2% 9.44 936 18 50.0% 10.00 1041 19 52.8% 10.56 1142 20 55.6% 11.11 1143 21 58.3% 11.67 1244 22 61.1% 12.22 1245 23 63.9% 12.78 1346 24 66.7% 13.33 1351 25 69.4% 13.89 1452 26 72.2% 14.44 1453 27 75.0% 15.00 1554 28 77.8% 15.56 1655 29 80.6% 16.11 1656 30 83.3% 16.67 1761 31 86.1% 17.22 1762 32 88.9% 17.78 1863 33 91.7% 18.33 1864 34 94.4% 18.89 1965 35 97.2% 19.44 1966 36 100.0% 20.00 20

Custom DiceFollowing are scans of some of the dice I have

remarked. I currently don't have a camera (even a camera phone) so I scanned them and haven't had time to remove the gray areas around them.

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Playing With 2d6

This is for people who don't want anything more complex than to roll two six-sided dice (2d6). Various games have been built around rolling 2d6 for resolution, including Traveler and MechWarrior.

Converting Modules to 2d6 SystemsSome people have fun making up lists of conversions

such as for armor-classes. The author prefers to develop a base system and convert modules to it without referring to the other game statistics. The statistics used in other games might be looked at to see what they intend, but what is really important is the approach to the game being used to play the module, not the game the module was designed for.

For example, the author starts with an armor class of 6 for all monsters and if he wants something to be tougher, he bumps it up. When dealing with NPCs, he looks at their description for ideas, but in the end he assigns ability scores and armor (if allowed) as he wants them.

The 2d6 Die RollThe author prefers to convert games to a d12 basis,

starting with a mid point of 7 or higher versus 11 or higher for a d20. When he uses a 2d6 roll, he uses a 1 to 12 base number range, letting the 2d6 roll speak for itself rather than trying to rejigger the numbers for the probabilities of 2d6.

A roll of two dice (2d6) is typically used for saving throws, to-hit rolls, and skill rolls. This die roll generates 11 numbers (2 to 12) with the median being 7. Individual numbers do not have the same chance of occurring with each die roll: the end points (2 and 12) have a 1 in 36 chance of occurring, while the mid point of 12 has a 1 in 6 chance of occurring.

The following compares a roll of 2d6 to a roll of 1d12: with a d12, each number has a 1 in 12 (8 ⅓%) chance of occurring.

2d6 ProbabilitiesCumulative % # 1d12

# Occurrences Prob % Asc Desc 1 8.3%2 1 2.8% 2.8% 100.0% 2 16.7%3 2 5.6% 8.3% 97.2% 3 25.0%4 3 8.3% 16.7% 91.7% 4 33.3%5 4 11.1% 27.8% 83.3% 5 41.7%6 5 13.9% 41.7% 72.2% 6 50.0%7 6 16.7% 58.3% 58.3% 7 58.3%8 5 13.9% 72.2% 41.7% 8 66.7%9 4 11.1% 83.3% 27.8% 9 75.0%

10 3 8.3% 91.7% 16.7% 10 83.3%11 2 5.6% 97.2% 8.3% 11 91.7%12 1 2.8% 100.0% 2.8% 12 100.0%

Total: 36 100.0%

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2d6 vs 1d12 Point by Point Comparison

0%

2%

4%

6%

8%

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12%

14%

16%

18%

1 2 3 4 5 6 7 8 9 10 11 12

number

per

cen

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2d6

1d12

2d6 vs 1d12 Cumulative Comparison

0%10%20%30%40%50%60%70%80%90%

100%

1 2 3 4 5 6 7 8 9 10 11 12

number

per

cen

t p

rob

abil

ity

2d6 1d12

Graphing the individual probabilities results in a pyramid for the 2d6 and flat line for the d12. The graph of the cumulative ascending probabilities reveals an s-shaped line versus a straight line:

What this is intended to point out is that a roll of 2d6 is not a flat die roll, although the cumulative percent can come close and match that of a d12 in certain cases.

Affect of 2d6 vs d12Using a 2d6 roll reduces randomness and increases

predictability, as explained in the use of 3d6. Most die rolls will be 6, 7, or 8. A 2 or 12 will be less common.

The Value of Pluses and MinusesEach number on a d12 has an 8⅓% chance of

occurring and hence many people realize that a +1 bonus is the equivalent of an 8⅓% increase.

When analyzing a 2d6 roll, the chance of different numbers occurring varies. For example, a +1 bonus added to 7 increases it to 8 with a roughly 14% increase while 1 added to 11 increases it to 12 for roughly 3% gain. Numbers past 12 involve esoteric math: consider how a 7 has a 58% chance of occurring with 2d6, which means an 8 has a 58% chance of occurring with 2d6+1, while a 13 has a 3% chance of occurring with 2d6+1. The math involved can be quirky: consider a roll of 2d6+3 that starts with a 10: 2 points increases it to 12 which is an 8% jump and then the extra point goes to 13 which is a 3% jump which is about 11%.

Keep in mind that in practical terms, the importance of any die roll is not the percentage but rather the number itself: an 8 is still an 8 and a 13 is still a 13 and they are typically compared to numbers from 1 to 12 on 2d6.

Using a d12 roll as a basis of comparisons, a bonus of 1 (8 ⅓%) is almost the same as a +2 bonus for a d20 roll; 2 (16 ⅔%) is a little over a +3; and 3 (25%) is a +5 bonus.

Abilities Scores And Their UsesThis discussion involves the typical game that uses a die

roll of 3d6 for ability scores (with various point buys and pick lists based on that).

Various games use various schemes for ability score bonuses. The following gives a pretty hefty bonuses for high scores (low scores are often rare; few people enjoy playing characters who are inferior).

Ability BaseScore Bonus/penalty1-3 -34-5 -26-8 -19-12 0

13-15 +116-17 +2

18 +3

The scale of the plus or minus is mainly important for to-hit rolls, saving throws, and skill rolls. Quantities are usually based on a d6 in the first place, so there is little need to adjust for them. Below is an example of a system with slight changes:

Prime Requisite Experience EffectScore 1 -5 6-8 9-12 13-15 16-18x.p. -20% -10% x1 +5% +10%x.p. x.8 x.9 x1 x1.05 x1.1

Score 1-3 4-5 6-8 9-12 13-15 16-17 18Charisma:Morale: 4 5 6 7 8 9 10Reactions -2 -1 -1 0 +1 +1 +2Retainers 0 1 2 3 4 5 6Constitution:Hit Point Rolls -3 -2 -1 0 +1 +2 +3Poison/Disease Saves -2 -1 -1 0 +1 +1 +2Dexterity:Initiative -2 -1 -1 0 +1 +2 +3Missile To-hit, fighter -2 -1 0 0 +1 +1 +2Missile To-hit, other -2 -1 -1 0 0 +1 +2

6

Score 1-3 4-5 6-8 9-12 13-15 16-17 18Armor Class -2 -1 0 0 0 +1 +2Strength:Brute Strength -3 -2 -1 0 +1 +2 +3Melee Damage* -3 -2 -1 0 +1 +2 +3Throwing Damage* -3 -2 -1 0 +1 +2 +3Melee to-hit, fighter -2 -1 0 0 +1 +1 +2Melee to-hit, other -2 -1 -1 0 0 +1 +2Wisdom:Save vs. Magic -2 -1 -1 0 +1 +1 +2Detect Lie -3 -2 -1 0 +1 +2 +3

Score Intelligence (Languages)1-3 Can only grunt and gesture crudely.4-5 Can speak racial language poorly; cannot

read/write.6-8 Can speak racial language well but read/write it

crudely; can speak common poorly but cannot write it.

9-12 Can speak and read/write racial language and common well

13 As 9-12 and can speak 1 more language14 As 9-12 and can speak 2 more languages15 As 9-12 and can speak 3 more languages16 As 9-12 and can speak 4 more languages17 As 9-12 and can speak 5 more languages18 As 9-12 and can speak 6 more languages

Armor ClassThere are two main systems for AC: ascending and

descending.

Descending Armor ClassOlder games started with a descending armor class

where higher was worse: unarmored creatures started at 9 or 10 and armor would reduce this to as low as 3 for plate armor and even lower. These games often used tables to look up to-hit numbers. Eventually they began using a THACO or THAC0 system (To-hit Armor Class 0), with the target's armor class subtracted from THAC0.

A different approach is to view armor class as a bonus to the attacker's to hit roll: thus, if a d20 roll + the target's armor class plus modifiers equal or exceeds 20, a hit is scored. Calculate a to-hit modifier for the characters by subtracting their THACO number from 20 or 21 as is desired. Note that some games use repeating 20s rather than 2 for the THAC0 for low hit die/level characters; you may have to manually assign THAC0s of 0 or -1.

Or, the formula can be used as: d20 + modifiers is a hit if it equals or beats the THACO.

Thus, you have:

1. table look-up2. THAC0 - armor class3. d20 + armor class + to-hit modifier >= 203. d20 + armor class >= THAC0

To use a descending armor class system for 2d6 games,

start with 5 as unarmored and apply armor effects:

ArmorNo Armor AC 5Leather AC 4Chain Mail AC 3Plate Armor AC 2

Shield Reduces 1 point

In this case, 2d6 + the target's armor class plus modifiers is a hit if it equals or exceeds 12.

Ascending Armor ClassThis is used in more modern system: the target's armor

class is the number that must be rolled or beaten to hit it. Some people might prefer to start with 6 as unarmored.

Armor Option #1 Option #2No Armor AC 7 AC 6Leather AC 8 AC 7Chain Mail AC 9 AC 8Plate Armor AC 10 AC 9Shield +1 +1

In d20 games there has been various approaches to the base armor class (unarmored): 10, 11, 12.

Softening the Effect of ArmorWhen rolling 2d6 (let alone a d12), armor can rapidly

become daunting.Following are two examples of how armor might be

treated - it is kept useful, but does not overwhelm the game. Doing this allows a tweak in giving fighters a bonus of 1 to armor class for their combat training.

Option #1Armor Asc. Desc. other effectsNo Armor AC 6 AC 5Leather AC 7 AC 4Chain Mail AC 7 AC 4 +1 saves versus dragon

breath, fireball, etc. (but not lightning)

Plate Armor AC 7 AC 4 +1 saves versus dragon breath, fireball, etc., + 6 hit points*

* Both maximum and current hit points are increased by 6; if the armor is removed, they both drop by 6. If current hit points drop below 1 the character is slain by the next hazard or monster they face, no die rolls allowed to save them.

Option #2Armor Asc. Desc. other effectsNo Armor AC 6 AC 5Leather AC 7 AC 4

7

Chain Mail AC 8 AC 3Plate Armor AC 8 AC 3 +1 saves versus dragon

breath, fireball, etc. (but not lightning)

8