The 3D6 System
The Storyteller calls for a roll when an action can fail and its outcome could change the adventure. The player then rolls three six-sided dice. A die scores a success when its result is no higher than the Ability selected by the Storyteller.
Modifiers
An advantage increases the roll to 4d6. Favorable circumstances, a relevant skill, or an ally's help can provide it.
A disadvantage, such as an injury, difficult terrain, or surprise, reduces the roll to 2d6. Advantage and disadvantage cancel each other when both apply. Modifiers of the same type do not stack, so a roll always contains between two and four dice.
A re-roll lets the player roll one die again, usually a die that did not score a success. Several re-rolls can apply to the same roll.
A useful Purr-ecious item or a relevant Cattribute grants one. The Storyteller can also award one for a clever solution.
Difficulty
| Level | Successes required | Examples |
|---|---|---|
| Easy | 1 | Getting up a tree, negotiating a small discount |
| Medium | 2 | Tracking a creature, crossing a slippery branch |
| Difficult | 3 | Escaping a bear, understanding human instructions |
| Legendary | 4 | Riding a bear, leaping from a cliff into a torrent |
Success and failure
- The roll reaches the threshold: the Kitten achieves the intended result.
- The roll scores successes without reaching the threshold: the player chooses between failure with no added consequence and success with a complication.
- The roll scores no successes: the action fails completely.
When a roll shows three identical dice, something good always happens to the Kitten, whether the action succeeds or not: a slightly better success, a failure with softer consequences, or a small extra unrelated to the action that moves the story along.
Open actions
An open action has no threshold set in advance. After the appropriate Ability roll, the Storyteller interprets the number of successes according to the task and situation.
Opposing actions
In a direct contest, such as a race, an eating contest or a woolball match, each character rolls the appropriate Ability. The highest number of successes wins.
On a tie, the Storyteller chooses between another roll and a draw. Some contests can be played over several rounds.
Long tasks
For tasks that take time under pressure, the Storyteller sets:
- the total number of successes needed, usually 4 for a fairly quick task, and as many as 20 for a long, exhausting one
- the time one roll represents, from a minute of work to an hour or even half a day
- if needed, the maximum time available or the cost of each period that passes
Several Kittens can work together by pooling their successes, or take turns if only one can act at a time.
Group actions
When all the Kittens act together and help each other, for example to climb a cliff, every player makes a roll with the appropriate Ability against the difficulty set by the Storyteller. If most of the Kittens succeed, the whole group succeeds.
The 3D6 System is based on an original idea by Croc and is used by other games: 
generic entry on Le Grog.