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*To*: tft@brainiac.com*Subject*: (TFT) H3 System Revisited: Skewing the Bell Curve*From*: <dwtulloh61@cox.net>*Date*: Fri, 5 Jan 2007 22:04:11 -0800*Reply-to*: tft@brainiac.com*Sender*: tft-admin@brainiac.com*Sensitivity*: Normal

SKEWING THE BELL CURVE One of the core premises of Melee/Wizard is its implementation of success or failure; you roll 3D6; a total of 5 or less means you succeed, 16 or more means you fail. The less likely the outcome, the more spectacular the result; a 3 is a magnificent success while an 18 is a disastrous failure. The combined probabilities of these rolls means that 5% of the time you are going to succeed in a task and 5% of the time you are going to fail. As a means of modifying this roll, TFT employs an "add or subtract a D6" method: if a task is more difficult, add a D6 (or two, or three...) and if easier, subtract a D6 from the roll. TFT still clings to this +/- 5% law however, so that if you are rolling 4D6, you have to consult a special table to determine your chances of auto success/failure, for 5D6 another chart, for 6D6 another chart, ad infinitim. If you are lucky enough to be rolling 2D6, well you still have a chance of auto success or failure, but now it is only if you roll a 2 or a 12. And some tasks (at the GMs discretion) are deemed to be so easy (or so hard) as to not require a roll at all. Such a system ignores a basic premise of reality: it is easier for skilled characters to perform simple tasks and harder for unskilled to perform more difficult ones. The TFT system flies in the face of that: no matter what your skill level, you are going to succeed or fail 5% of the time. In July 2000, I proposed a new system of modifying dice rolls to address this problem: it was dubbed the "Highest Three" system. Basically, the idea was that if you were attempting a 4D6 roll, you rolled the 4D6 as normal but instead of totalling all of the dice, you totalled only the highest three, which gives you a result of 3-18 which you then interpret as per the basic rules. The system had the benefit of being easy to implement and was infinitely expandable on both ends of the spectrum. The proposal generated some discussion and, despite its initial appeal, it was eventually abandoned due to the steepness at which it generated success/fail results. After a lot of thought at trying to save the system, I've come up with a method which works and, though a bit more difficult to implement, is still playable and generates good results. In order to implement it, a GM will need a red die, a green die and several white dice. Before rolling the dice, the GM determines the difficulty level of the roll by summing the relevant disadvantages and subtracting the relevant advantages. Under the old TFT method, this was adding and subtracting a D6: A character wishes to avoid an ambush, he has the advantage of Alertness which produces a difficulty level of -1; A character searches for a specific herb, it is rare in these parts (two disadvantages) but the character has Nature Lore (one advantage) which gives a difficulty level of +1. The GM then throws the red die, the green die and the required number of white dice and consults the following table: DL #W Red Result P(5-) P(16+) ... -4 5 Sum Lowest 3 of 5 White dice .2342 .0027 -3 4 1-3 Sum Lowest 3 of 4 White dice .1823 .0072 4-6 Sum Lowest 3 of Green & 4 White dice -2 4 Sum Lowest of 4 White dice .1304 .0116 -1 3 1-3 Sum 3 White dice .0884 .0290 4-6 Sum Lowest 3 of Green & 3 White dice 0 3 Sum White dice .0463 .0463 +1 3 1-3 Sum 3 White dice .0290 .0884 4-6 Sum Highest 3 of Green & 3 White dice +2 4 Sum Highest 3 of 4 White dice .0116 .1304 +3 4 1-3 Sum Highest 3 of 4 White dice .0072 .1823 4-6 Sum Highest 3 of Green & 4 White dice +4 5 Sum Highest 3 of 5 White dice .0027 .2342 ... This may seem confusing at first but it gets easier to use over time and has the advantage of allowing the GM to interpret the result in just one throw of the dice. The long and short of it is this: if the DL is even, use only the white dice. If the DL is odd, then the red die is used to interpolate the results between the two surrounding DL values. Dan ===== Post to the entire list by writing to tft@brainiac.com. Unsubscribe by mailing to majordomo@brainiac.com with the message body "unsubscribe tft"

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