3d20 system

The 3d20 system is the role-playing game system used in Neuroshima and Monastyr. Like the d20 System, it uses twenty-sided dice, but unlike that system it most typically uses three.

When a test is required, the Gamemaster, names the skill which is going to be tested (or a raw attribute, if no skill is available for the activity the character is trying to perform). He also sets a difficulty level for the test, which modifies the attribute value (reducing or improving it). Then, the character's skill level is taken into account - if the character does not have any skill levels in the given skill, (in case of Neuroshima) the difficulty level is raised by one, or (in case of Monastyr), all the three rolls (not two) have to be lower than the tested attribute. Otherwise, the player can subtract a total of his character's skill levels in that skill from any of the three dice rolls, each separately.

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