Game Mechanics

Game Mechanics

Sin City uses the Silhouette RPG system. This is the same set of mechanics as are found in Dream Pod 9's Heavy Gear RPG. Players who want to know everything there is to know about the system should check out that game. However, this overview should be enough to get players up and running.

The Basic Rule

All rolls work as follows:

  • Attribute + Ability + Modifier Dice = Dice Pool
  • Roll as many d6s as you have dice in your pool
  • Keep your highest die
  • For each additional 6 past your first, add +1 to your final score
  • Add any modifiers to your final score
  • You're done.

For instance, someone with a 1 Fitness and a 1 Athletics might be trying to leap from one building to the next. The gamemaster declares this to be a challenging but not especially difficult task, and assigns it a difficulty number of 3. The player rolls two dice. If either one of them comes up a three or higher, the character makes a successful leap.


If all your dice come up as 1, then your character has badly fumbled the action. The precise effects of the fumble are up to the gamemaster.

Automatic Success

If your character is in a non-stressful situation, you may choose to assume an outcome of 2 + your skill level. For instance, with a 2 Athletics you may assume your character automatically passes any non-stressful skill test at difficulty 4 or less.

Typical thresholds

  • 1: Effortless tasks where success is pretty much automatic.
  • 2: Routine. Finding your car keys in the morning.
  • 3: Easy. Navigating freeway traffic on your way to school.
  • 4: Moderate. Running an eight-minute mile between the parking lot and your class.
  • 5: Challenging. Pulling an "A" on your Classical Greek final exam.
  • 6: Difficult. Pulling an "A" on your Classical Greek final exam, after partying hard the night before.
  • 7: Very difficult. Pulling an "A" on your Classical Greek final exam, after blowing off the class for the semester.
  • 8: Extremely difficult. Wait, this is Classical Greek? You thought it was Classical Latin!
  • 10: Near impossible. Explaining to the professor what just happened.
  • 12: Divine intervention. Getting the professor to accept your explanation.

Margins of Success

The difference between what you rolled and what you needed is the margin of success (or failure, as the case may be). The more you succeeded or failed by, the greater the significance of your success or failure. A margin of zero means you just barely succeeded; a margin of three or more means you made it look easy.

Opposed Actions

For opposed actions, both parties make relevant rolls. Whichever one scores higher wins, with a margin of success given by the difference between their rolls.

Extended Successes

Sometimes, more than one success is necessary. For instance, writing a complex piece of software might require a target number of 7, and one roll allowed per day. Once you accumulate the necessary number of successes, you're finished.

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