# Talk:D20.00 Variant Rules (D20.00 Decimal Rules Supplement)

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## Rolling very big dice[edit]

Actually, for the core die-rolling, there's one easy way to replicate what you want to do WITHOUT computers, based on the old d% basics.

Percentile dice are essentially d100s, and produce results from 0 to 99 (or 1 to 100, depending on how '00' is interpreted) via 2d10, distinguished somehow (my preferred is that one is labelled 0-9, and the other 00-90). This, by probability, gives a 1% chance for each number--the chance for a 0 on these dice is 1%: 10% for a 0 on the first, times 10% for the 00 on the second, equals 1% (.1 x .1 = .01). Qaianna 02:22, 4 January 2007 (MST)

- I MoI'ed the author, User:Pz.Az.04Maus, he should respond soon. --Green Dragon 16:02, 4 January 2007 (MST)
- Answer below, but I'm not really sure of what your second half refers to, Unfortunantly (BDI (Big Dumb Idiot) here). Is there a way that you could clarify?--Pz.Az.04Maus 16:20, 4 January 2007 (MST)

## Probability[edit]

What this mechanic seems to do is change the results of a d20 from 1-20 to 0.01 to 20.00 ... and this can be done by rolling a d20 plus the percentiles (generally sold in the same polyhedral dice sets in stores, too).

Thus, getting the 20.00 result would take: 5% x 10% x 10% = 0.05% chance. This also gives you 20 x 10 x 10 = 2000 results, and that would give you an 'average' of 10.005.

Also, there's these statements: 'Since every number has the same chance of being hit, and since there are now 1980 more possible hits to choose from, the chances of hitting a certain number, while the same, is not so guaranteed, because there are many more possibilities that the die can roll upon, not just a few.' This seems to be using intuition to guide probability, which one does at risk ...

The chance of rolling, say, a 10 is lowered significantly under the new system. The chances of rolling OVER 10 are NOT changed, though.

If your results are 0.01-20.00, then 1,000 of the results are 10 or less, and 1,000 are over 10. If your results are 1-20, then 10 of them are 10 or less, and 10 are over 10. 1,000/2,000 = 10/20 = 50%. The coin-flip 'ideal' is merely 1/2, or 50% again.

Parsing the new dice needed is a bit awkward, too, and honestly I don't see the benefit of this, all for changing the average roll from 10.5 to 10.005.

Also, how will this affect critical hits and misses? Is anything over 19.00 a threat? That sort of distribution would preserve the standard d20 chances (5%). Qaianna 02:22, 4 January 2007 (MST)

- I MoI'ed the author, User:Pz.Az.04Maus, he should respond soon. --Green Dragon 16:02, 4 January 2007 (MST)
- With the d20 and the percentage, I saw an even worse skew towards 11.05 with the d20 and the d100. It wouldn't have done what I wanted it to. I had thought of this, but then I saw the results, and I didn't like it. --Pz.Az.04Maus 16:17, 4 January 2007 (MST)

- However, since that technically these are dice (even though it's a PC Program), it thus gains the average of the lowest possible and the highest possible. For a d20, that is 10.5. For a d2000, a d2000/100 gives you the chance from 0.01 to 20.00. Add those together, divide by, it's closer to 0 for rolling a 10. It isn't 0-20, but is close enough. also, having 1-20 gives you 19 possible chances, not 20.--Pz.Az.04Maus 16:17, 4 January 2007 (MST)

- The Benefits are hard to see, I'll admit. However, it's just really a theory that might be used once in a while by someone who wants to lessen the possibility of a skewed result. I'm also not a very good mathematician (I'm still In Highschool, after all), but this is plausable. It's your thought, however, that there's no real benefit to extra work. I feel that there's a slight benefit that is worth it, however small. --Pz.Az.04Maus 16:17, 4 January 2007 (MST)