Core Mechanics

Most modern games have a central mechanism that governs how players usually interact with the world - D&D 3.x had the d20 roll, GURPS has the 3d6 roll, FATE has its d10s, and so on.  Now, OD&D and AD&D featured different interaction mechanics for different scenarios - martial combat and saving throws used the d20 roll-under, as did ability checks, but the all-important reaction roll was determined by 2d6+Cha mod.  I'm sure there are other mechanics I am forgetting, since I am not as familiar with OD&D and AD&D.

All of these mechanics (except FATE) function similarly: [di(c)e roll] + [modifier] ~ [difficulty value] (where ~ is a relation corresponding to either greater-than-or-equal-to or less-than-or-equal-to, and the modifier can either be a positive number or a negative number, usually dependent upon the identity of ~).  I don't think this is controversial.  Typically, the DV will increase with the scale of the feat required, and the modifier will correlate with the character's ability for that task (as the character gets better at something, their magnifier will increase).  Usually, the dice used will stay fixed, although FATE and dice pool systems are the obvious exception to this; such systems tend to change the number of dice rolled according to character skill and demand a number of 'successes' depending upon the difficulty of the task attempted (and the value required to count as a 'success' can also vary based upon this task difficulty).  For example, in FATE, a character with 4 Brawl rolls 4d10 when attempting to apply brute force in combat, and count as a success any die resulting in 8, 9, or 10, a failure any die of value 1, 2, or 3, and neutral any die in between (failures cancel out successes).  Depending upon the defenses of the target, the number of successes required will fluctuate.

Lastly, I wanted to discuss the system presented here.  As I understand it, it is the current foundation of C's current skill system over on www.hacknslash.BlogSpot.com, and it was highly influential in the creation of the Prodigy discipline system.  The gist of it is that there are different tiers of experience and that as one progresses these tiers, one rolls a larger and larger die.  This is a truly elegant skill system.  To me, though, it does have one unfortunate flaw.

In the real world, three things tend to happen as a person becomes more skilled.  The first is that the person is able to accomplish more impressive feats - a skilled cook can prepare a much more remarkable meal than a novice from the same ingredients.  Second is that the person's failures tend to be less catastrophic - a novice's meal might actually poison you while a skilled cook's failure might just taste bad.  These first two things are accounted for in most of these systems - rolling a larger die or adding a larger number does increase the character's likelihood to succeed, and failed attempts will likely fail by less, so that works.

The third thing, though, I think is perhaps most important: skilled characters can more reliably produce the same results.  One of the major problems of rolling single dice is that each value is equally likely - rolling a larger die increases the mean result, but critical failures are just as likely as critical successes, which are just as likely as any other possible value.  For 3.x, I use 2d10 instead of 1d20 for this very reason.  It is the combination of higher quality and more reliable work that makes skilled people more valuable.

If you watch reality TV shows like Project Runway, Make Me a Supermodel, Top Chef, etc. you'll see the judges weighing which is more important - the capacity to do great work or the ability to consistently create a good-quality product.  Usually, the reliable people beat out the hit-or-miss geniuses.  It is this last quality that is lacking from most resolution mechanics (GURPS, of course, is based on the 3d6 bell-curve but it has other issues [since most actions are opposed by other individuals and success is reliably attained, most turns are spent hoping the opponent screws up instead of wishing for the character to do well]).

Prodigy seeks to increase both consistency and the level of achievable results by summing an increasing number of dice together as the character improves.  There are 6 tiers of skill: Novice, Apprentice, Journeyman, Specialist, Master, and Grandmaster.  Someone with Novice knowledge of the skill is essentially untrained at it, whereas Grandmasters can perform superhuman feats (a la minor superheroes, demigods of myth, etc.).  Tasks are rated along these criteria as well, so there are Apprentice difficulty tasks, Specialist difficulty tasks, and so on.  The following table shows the dice rolled for each tier and the difficulty value for each category.

Discipline Level	Notches	Dice Rolled	Difficulty Value
Novice	0	1d6	3
Apprentice	1	1d4+1d6	6
Journeyman	3	2d4+1d6	9
Specialist	6	2d4+2d6	12
Master	10	3d4+2d6	15
Grandmaster	15	3d4+3d6	19

Discipline Level	Notches	Dice Rolled	Difficulty Value
Novice		1d6	3
Apprentice		1d4+1d6	6
Journeyman		2d4+1d6	9
Specialist		2d4+2d6	12
Master		3d4+2d6	15
Grandmaster		3d4+3d6	19

Now, the mean value of each roll is also the mode  (except for novices, which is appropriate).  Notches refer to how much training is required to reach the next level of skill.  I'll keep those numbers to myself for now, since explaining that would take a great deal more time and space.

Hopefully these thoughts stimulate your own brains and/or whet your appetite for Prodigy.