Post by gamedave on Oct 26, 2007 9:42:04 GMT -5
Here's the core mechanic:
Roll a d10. Apply modifiers. Consult the Universal Table:
0 or less: Critical Failure
1-4: Standard Failure
5: Marginal Failure
6: Marginal Success
7-10: Standard Success
11+: Critical Success
Natural 1: turns a Marginal or Standard Failure into a Critical Failure, no effect on Successes.
Natural 10: turns a Marginal or Standard Success into a Critical Success, no effect on Failures.
That's it. Pretty similar to the current system, except it only uses one die instead of 3+. Why a d10 instead of 3d6? I'm glad you asked.
No more Ranks and Edges. Instead, Abilities and such are rated with a single number Rank. Human-level Abilities range from 1 - 9, with 5 being the default average. Super-Abilities and such can range up to 25 or higher.
You roll the die, add your Rank, and subtract the Difficulty, then consult the Universal Table. On this scale, a d10 works out well - at default value of 5, a person has an outside shot of making a 9 (maximum human ability) Difficulty. In terms of the old system, you have a chance if you roll at a Difficutly of 1 Rank above yours, but the math prevents you from a chance at 2 or more Ranks difference.
I could have used d6s, and really wanted to (I really like the idea of a generic poker and dice pack being the only necessary game accessories), but the math steered me to d10s.
A single d6 just doesn't give enough of a range.
2d6 has about the same range as a d10, but the curve of results doesn't work. I want, everything else being equal, for a characer rolling against a Difficulty equal to his Rank to have a 50/50 chance of success, and a smooth distribution of Success Levels. With a single die, you have an even number of possible results, and the die can't roll the median (5.5 for a d10), which gives you a smooth distribution of Success Levels (1 in 10 for a Crit, 3 in 10 for a Standard, 1 in 10 for a Marginal). With 2d6, you get a median of 7 - which is also the mean and the mode - if the 7 is a success, characters will succeed most of the time, if it's a failure, they'll fail most of the time, and Success Levels can't be smoothly distributed.
3d6 restores the smoothness - the median is 10.5, so Success Levels can be evenly distributed around it. But the scale gets huge. In order to get the same effect, where an average Rating can just make a max human Difficulty, but can't make a superhuman Difficulty, the range of human level ranks would have to go from 1 - 15, and to cover the same range of superhuman abilities as 10 - 25 on a d10 would require a range of 16 - 43 on 3d6. Also, the breakpoints get messier. On the d10 scale, odd numbers are natural breakpoints, and every +4 points (the max Difficulty a rating can make) is an odd number. From the default average of 5, we get break points at 1, 5, 9, 13, 17, 21, 25. On the 3d6 scale, the breakpoints are at 1, 8 (default average), 15 (max human), 22, 29, 36, 43. Ick.
So, anyway, a d10.
Roll a d10. Apply modifiers. Consult the Universal Table:
0 or less: Critical Failure
1-4: Standard Failure
5: Marginal Failure
6: Marginal Success
7-10: Standard Success
11+: Critical Success
Natural 1: turns a Marginal or Standard Failure into a Critical Failure, no effect on Successes.
Natural 10: turns a Marginal or Standard Success into a Critical Success, no effect on Failures.
That's it. Pretty similar to the current system, except it only uses one die instead of 3+. Why a d10 instead of 3d6? I'm glad you asked.
No more Ranks and Edges. Instead, Abilities and such are rated with a single number Rank. Human-level Abilities range from 1 - 9, with 5 being the default average. Super-Abilities and such can range up to 25 or higher.
You roll the die, add your Rank, and subtract the Difficulty, then consult the Universal Table. On this scale, a d10 works out well - at default value of 5, a person has an outside shot of making a 9 (maximum human ability) Difficulty. In terms of the old system, you have a chance if you roll at a Difficutly of 1 Rank above yours, but the math prevents you from a chance at 2 or more Ranks difference.
I could have used d6s, and really wanted to (I really like the idea of a generic poker and dice pack being the only necessary game accessories), but the math steered me to d10s.
A single d6 just doesn't give enough of a range.
2d6 has about the same range as a d10, but the curve of results doesn't work. I want, everything else being equal, for a characer rolling against a Difficulty equal to his Rank to have a 50/50 chance of success, and a smooth distribution of Success Levels. With a single die, you have an even number of possible results, and the die can't roll the median (5.5 for a d10), which gives you a smooth distribution of Success Levels (1 in 10 for a Crit, 3 in 10 for a Standard, 1 in 10 for a Marginal). With 2d6, you get a median of 7 - which is also the mean and the mode - if the 7 is a success, characters will succeed most of the time, if it's a failure, they'll fail most of the time, and Success Levels can't be smoothly distributed.
3d6 restores the smoothness - the median is 10.5, so Success Levels can be evenly distributed around it. But the scale gets huge. In order to get the same effect, where an average Rating can just make a max human Difficulty, but can't make a superhuman Difficulty, the range of human level ranks would have to go from 1 - 15, and to cover the same range of superhuman abilities as 10 - 25 on a d10 would require a range of 16 - 43 on 3d6. Also, the breakpoints get messier. On the d10 scale, odd numbers are natural breakpoints, and every +4 points (the max Difficulty a rating can make) is an odd number. From the default average of 5, we get break points at 1, 5, 9, 13, 17, 21, 25. On the 3d6 scale, the breakpoints are at 1, 8 (default average), 15 (max human), 22, 29, 36, 43. Ick.
So, anyway, a d10.