All common skills fall under one of the three basic proficiencies: Athletics, Cunning, or Vigilance.  Since little training is required  to gain these skills, they are static based on the description, which means that the workings of the skill do not change as the character advances. Each individual skill has an associated attribute that is used as its base score, adding any acquired skill tree points and/or modifiers to determine its total score.

Unlike Specialties, Novice skills from all three of the Proficiency skill trees are immediately available for purchase during character generation, based on the number of build points remaining. Additional Proficiency skills may be purchased as the character advances. Expert and Master level skills can be purchased after a specific number of skill tree points have been gained after level advancement, and may require some specific prerequisite skills.

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