Difficulties for dice rolls are normally rated on the following scale:
| Difficulty | Typical difficulty value | Meaning |
| Trivial | 0 or less | An average character without any familiarity with the skill can pretty much guarantee success under most circumstances. |
| Very easy | 1-2 | An above
average character or one with some familiarity with the skill should
automatically succeed.
An average character with no skill might succeed. |
| Easy | 3-4 | A skilled
character should automatically succeed.
A competent character is likely to succeed. An average character with no skill is likely to fail. |
| Average | 5-6 | A highly
skilled character should automatically succeed.
A skilled character is likely to succeed. A competent character is unlikely to succeed. An average character with no skill will almost certainly fail. |
| Difficult | 7-8 | An expert
character should automatically succeed.
A highly skilled character is likely to succeed. A skilled character is unlikely to succeed. A competent character will almost certainly fail. An average character with no skill will definitely fail. |
| Very difficult | 9-10 | A character
with mastery of the skill should automatically succeed.
An expert character is likely to succeed. A highly skilled character is unlikely to succeed. A skilled character will almost certainly fail. Anyone who is less than skilled will definitely fail. |
| Extremely difficult | 11-13 | A character
with mastery of the skill is likely to succeed.
An expert character is unlikely to succeed. A highly skilled character will almost certainly fail. Anyone who is less than highly skilled will definitely fail. |
| Heroic | 14-16 | A character
with mastery of the skill who specialises in this area is likely to
succeed.
A character with mastery of the skill who does not specialise in this area is unlikely to succeed. An expert character will almost certainly fail. Anyone who is less than an expert will definitely fail. |
| Unbelievable | 17-19 | A character
with mastery of the skill who fully specialises in this area is likely
to succeed.
A character with mastery of the skill who partially specialises in this area is unlikely to succeed. A character with mastery of the skill who does not specialise in this area will almost certainly fail. Anyone who is less than a master of this skill will definitely fail. |
| Nearly impossible | 20-24 | The very best
of characters would be unlikely to guarantee success.
Even a character with mastery of the skill who fully specialises in this area would be unlikely to succeed. Anyone who is less than a master of this skill specialising in this area will almost certainly fail. |
| Impossible | 25 or more | Even the very
best of characters would be unlikely to succeed.
Anyone less than the very best will almost certainly fail. |
Sometimes the difficulty value for one character's dice roll will be the dice roll result from another character's dice roll. In other words, the higher result wins. For example, two characters are arm wrestling; both characters make dice rolls - the character with the higher dice roll result will push the other character's arm down. Half values on dice roll results are particularly important in these contests.