User:Kydo/d6differential

D6 Differential is a dice-based randomized resolution mechanic. It is based on a notation of 2d6-2d6, which produces a normal distribution with a range from -10 to +10, with 0 being the median and most likely result. The positive dice (the first two) represent your personal effort, talent, and luck. The negative dice (the other two) represent all opposing factors.

On a given engagement, (check) the notation may be modified to represent changing circumstances, effectively the same as advantage and disadvantage in 5e, but instead of an exponential effect as seen with stacked advantage, this system instead skews the range and mean up and down between -17 and +17 while maintaining a normal distribution. (With the exception of 1d6-1d6, which is bilinear)

+1 positive die represents you having some personal advantage.

-1 positive die represents you having some personal disadvantage.

+1 negative die represents the target having some advantage to resist your act.

-1 negative die represents the target having some disadvantage to resist your act.

Sometimes, a single factor may affect both sides of a task. For example, in a swordfight, having the upper ground would advantage you and disadvantage your target at the same time. However, if either of you were ill, that would only disadvantage the individual, because being comparatively "not sick" is not a deviation from a normal relativistic state of things.

Here is an anydice presentation of all probability charts generated by this system.

Checks are made with modifiers of course. Your abilities, (ripped shamelessly from D&D) can apply a modifier of -5 to +5 and are generated by rolling 1d6-1d6. Skills can additionally add as much as +5 in skill ranks to a check. If any equipment is used, it can provide up to +5 depending on quality. Finally, magic can provide up to +5 to a check, either through a buff or through equipment enchantment. In total, the maximum bonus you can receive to a roll is 20. That means the highest possible roll on 3d6-1d6 with maxed out modifiers is 37.

This resolution mechanic does not use DCs. Rather, it is based on the Omni-System's omnichart. The chart'shows range is -40 to +40. "Challenge" is a penalty to the roll which may be applied by the DM, but typically is not unless the target has relevant modifiers. When a player rolls, they compare their result to the omnichart to determine both success and effectiveness. Success is anything above 0, while failure is 0 and below. Effectiveness is determined by deviation from 0. The higher you rolled, the more effective you were, while the lower you rolled, the less effective you were. Very bad rolls have consequences, as per fumbles, while very good rolls have bonuses, as per criticals.

+40 = success with a bonus

+35 = success with a bonus

+30 = success

+25 = success

+20 = success

+15 = success with a consequence

+10 = success with a consequence

+5 = both a consequence and bonus, but failed

0 = both a consequence and bonus, but failed

-5 = both a consequence and bonus, but failed

-10 = failure with a bonus

-15 = failure with a bonus

-20 = failure

-25 = failure

-30 = failure

-35 = failure with a consequence

-40 = failure with a consequence