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207 votes
Accepted

Rolling a D10 (0-9) for hitpoints. What do I get with a zero?

A zero on a d10 counts as 10. This isn't clearly specified in the 5th edition rules, but is clearer in earlier editions of the game, and widely understood among long-time RPG players. However, we can ...
Quadratic Wizard's user avatar
201 votes
Accepted

Does microwaving a die significantly alter its balance?

It doesn't do anything. As a chemist, I had to give this a try. First, I started with a die that had a clear bias toward ~18, according to the saltwater test. The first picture is the initial drop ...
Icyfire's user avatar
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101 votes
Accepted

Why do most people consider a "00" and a "0" on a percentile roll a 100?

In common practice a d100 is effectively a 0-99 roll, with the stipulation that 0 be treated as 100 The game needs a way to roll 1 to 100 with equal chances, and no chance of getting zero. Let's ...
Valley Lad's user avatar
  • 7,595
97 votes

Is there any known limit for how many dice RPG players are comfortable adding up?

So, I am a freelance game designer and I’ve worked on a couple of systems and with a couple of design teams, but I am a “professional” only in the strictest sense (I have been paid for my game design ...
KRyan's user avatar
  • 353k
93 votes
Accepted

Player may be manipulating die rolls, but I'm uncertain. How do I approach the situation?

Use a Rolling Tray I don't want to accuse someone of cheating if they were not, but I also don't want cheating to continue if it is in fact occurring Since another player has already mentioned ...
KorvinStarmast's user avatar
90 votes
Accepted

What dice mechanic gives a bell curve distribution that narrows and increases mean as skill increases?

(SKILL+CONSTANT) dX, keep highest CONSTANT I don't know exactly the behavior you're going for, so there'll be a few arbitrary numbers in my example: skills can be ranked from 0 to 5 dice rolled are ...
nitsua60's user avatar
  • 102k
84 votes
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How to approximate rolls for potions of healing using only d6's?

Let's not overcomplicate it: a simple Nd6 + X formula will work just fine. Specifically, the effects of Greater (4d4 + 4) and Superior (8d4 + 8) healing potions are quite closely replicated by ...
Ilmari Karonen's user avatar
82 votes
Accepted

What is the difference between rolling more dice versus fewer dice?

From what I can gather what you're asking, you want to know the probabilistic difference between rolling 10d10 and 5d20. You've rightly pointed out that each roll has the same maximum and that each ...
Premier Bromanov's user avatar
80 votes

Rolling a D10 (0-9) for hitpoints. What do I get with a zero?

You are correct. Many old school d10s are marked 0-9 but you count the 0 as 10. If he doesn’t listen to reason, next level use one of the d10s marked 00-90 instead and demand your 45 or so hit ...
mxyzplk's user avatar
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76 votes
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How can I help players learn to tell apart the standard polyhedral dice?

Short answer: really, practice is the only answer It's like any kind of memorization task, eventually you're going to get it, and you'll have trouble until then. But there are ways to make the ...
Polisurgist's user avatar
  • 7,846
76 votes

Does the chance of rolling a 1 in a pool of d10s increase as the number of dice increases?

Yes it does. Your instinct is right. The more dice, the more likely you are to roll some 1s. If I'm reading you right you're just interested in whether any 1s appear in your rolled pool. It may not ...
nitsua60's user avatar
  • 102k
69 votes
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What does dice notation like "1d-4" or "1d-2" mean?

GURPS uses 6-side dice for practically everything. It's more economical to refer to them as simply "d" rather than "d6." GURPS uses six-sided dice only […] GURPS uses the "...
Alex P's user avatar
  • 29.2k
68 votes
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What are the statistical implications of doubling damage on crit instead of doubling the dice rolled?

Given the example of (2d6)×2 (henceforth referred to as 'Doubled Damage') vs (4d6) (referred to as 'Doubled Dice'): When you double the damage rolled instead of doubling the dice rolled, you ...
LegendaryDude's user avatar
67 votes
Accepted

Is it possible to emulate common polyhedral dice rolls using just a d6, and if so, how?

It's pretty trivial if you allow occasional discarding of rolls/rerolls. d2 (gonna need this later): if result is odd, read as a 1. If result is even, read as a 0. d4: discard any results of 5 or 6.* ...
nitsua60's user avatar
  • 102k
66 votes
Accepted

Dice Rolling Method Fairness

This is a classic clustering fallacy Wikipedia defines the clustering fallacy as: ...the tendency to erroneously consider the inevitable "streaks" or "clusters" arising in small samples from ...
Icyfire's user avatar
  • 63.7k
66 votes

Simulating these special dice on more regular dice

Look at the pips a certain way Tell your kids that the pips on the dice represent where you hit. A pip in the center means that you hit on-target, a pip on the sides means that you missed. As special ...
CR Drost's user avatar
  • 1,671
65 votes

How to let my players fail their rolls intentionally, but covertly?

You might want to take some inspiration from the game Paranoia.* In particular, instead of trying to avoid hidden notes, make note-passing between the GM and players a common and ubiquitous mechanic ...
Ilmari Karonen's user avatar
62 votes

Player may be manipulating die rolls, but I'm uncertain. How do I approach the situation?

Talk to your players Seriously. This is the very first step. Do not accuse anyone, just talk. There may be many reasons for cheating on dice: Failed roll ruined otherwise good plan that had 90% ...
Mołot's user avatar
  • 24.6k
60 votes
Accepted

Help me identify these 20-sided dice with assorted numbers from 4 to 72

I went and Googled for the numbers, and the first (and currently only) result was US patent 7815191B2 titled "Equals: the game of strategy for the basic facts". The abstract reads: "...
Ilmari Karonen's user avatar
57 votes

Can a Circle of the Stars Druid roll a natural d3 (or other odd-sided die) to bias their Cosmic Omen roll?

The rules assume you only have a standard polyhedral set. It seems abundantly clear to me that the intent is for the die to have an even numbers of sides. The feature’s outcomes are based on odd or ...
Thomas Markov's user avatar
56 votes
Accepted

Is there a name for this 20 sided die with two 1s, two 2s, etc?

Gamescience, a dice manufacturer, calls such a die simply a d20 0–9 Twice. Yours appears to be this one, and, as of this writing, it appears you can buy more. However, you may not need to. The owner ...
Hey I Can Chan's user avatar
55 votes
Accepted

Is GameScience's non-cylindrical seven-sided die a balanced/fair die?

The real experiment is difficult The linked dice in the question are out of stock, so only people who already have a lot of these dice and are willing to do the statistical tests can give the "...
Icyfire's user avatar
  • 63.7k
54 votes

Is it stated in the rules to be standard practice to hide rolls in 3.5e?

DM Lies and Fudging rolls To begin I want to cover the idea of fudging a roll. It may be considered controversial and all to many people, but it's both advised and explained in the 3.5e DMG on page ...
Zakier's user avatar
  • 2,196
52 votes
Accepted

What are the odds of rolling high all the time?

This may not be as unlikely as you think Preamble: Probability is Hard So distributions like this are tricky, because a lot of people assume, wrongly, that they only need to calculate the odds of ...
Xirema's user avatar
  • 52.7k
48 votes
Accepted

How to let my players fail their rolls intentionally, but covertly?

Secret Rolls You could simply ask that the players roll all of their checks in secret, then tell the other players the result. The success of a lie depends on the player's bluffing skills. You can ...
Ladifas's user avatar
  • 8,979
48 votes

Is GameScience's non-cylindrical seven-sided die a balanced/fair die?

No (With 99.5% Confidence) I purchased 5 of these dice to test their fairness. I rolled the dice 2250 times (450 sets), by hand in the dice bowl pictured above, and recorded the results. Face Count ...
Mark Omo's user avatar
  • 1,570
47 votes

Simulating these special dice on more regular dice

Map the answers to the face of a 6-sided die There are exactly 6 faces listed for your dice. They can thus be replaced by any fair six sided die by creating a translation table such as: $$ \begin{...
TimothyAWiseman's user avatar
46 votes

Why do most people consider a "00" and a "0" on a percentile roll a 100?

That method of rolling percentile dice actually pre-dates D&D. Reading percentile dice in this manner pre-dates D&D, and has been used consistently in the rules throughout editions of the ...
Quadratic Wizard's user avatar
46 votes

How to make a device to randomly choose one of three possibilities, with caveat that sometimes one of them is not available?

In general, a deck of cards is useful to select a choice from a menu that excludes prior choices. In this particular case, choose three playing cards to represent the monster's possible actions. On ...
sptrashcan's user avatar
  • 4,425

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