Of Waves and Dragons
The following is a short description of how the die system works in Pendragon. It is the same for skills, abilities, passions and traits. There are two types of rolls in Pendragon the opposed roll and the unopposed roll.
A character with a sword skill of 13 must roll and D20 and get under a 13 to succeed in striking an object. Any roll under the skill, passion or trait score is considered a success with a roll that equals the skill, passion or trait score is a critical success. Rolls over the score are considered a failure and a roll of 20 is considered a fumble. Rolling the exact number is considered a critical success.
When two characters are attempting an opposed task both must roll and succeed the check but the player that succeeds with a highest die roll is the winner of the check. Critical successes always win against a non-critical success. If both characters roll a critical then the roll is considered a tie. For example: Joe and Mark are racking horses. Joe has a riding score of 10 where mark has a riding score of 14. Joe rolls a 9 where Mark rolls a 4 on their riding checks and so Joe wins the race.
During the course of the game skills, passions and traits can have their value raised to and past 20. When a score reaches 20 then the funble result is changed to 1 and 20 is now the critical success value. When a score goes above 20 each point above 20 grants a +1 to the roll. Any results of 20 or higher are critical successes. For example Joe and Mark are racing again sometime later in their lives. Joe has worked hard and has raised his riding skill to 23 where Marks has a score of 16. Joe rolls a 15 on the dice and adds 3 (23 – 20 = 3) for a total of 15 beating Marks roll of 14.
Traits have one extra caveat when it comes to the die system. Typically when a trait such as Chaste is checked and failed the opposing trait, in this case Lustful, is then checked. If the second Trait is passed then the character acts in this case Lustfully. If both are failed then the character may choose freely how they would like to react to the situation.