Potestas
Skills are specific applications of Characteristics, such as using your Reflexes to avoid being hit and using your Intelligence to interpret a document in a foreign language. The Skill bonus represents the effect of experience and training on the character's innate talent for that task or activity (i.e. the Characteristic modifier). Skill bonuses stack with a Characteristic modifier and may be increased by characters as desired: there is no upper limit for Skill bonuses other than that set by the GM.
There are three types of Skills: Inherent, Acquired and Specialised.
Inherent Skills are possessed by all people. Everyone is capable of trying to hit another person or of trying to walk quietly and unobtrusively. Inherent Skills are still learned (e.g. gambling), and characters may convert them into Acquired Skills. Otherwise, characters always have a score for Inherent Skills. Cost: 1 point for +1.
Acquired Skills are not universally possessed, and must be obtained by performing specific activities that most people do not undergo. What these Skills are will vary according to the campaign setting: Literacy, for example, is an Acquired Skill in most pre-modern settings, but might be considered an Inherent Skill in a modern setting. Characters who do not have an Acquired Skill may still attempt to use the Skill, but are treated as having the minimum possible Characteristic modifier for their race (usually -7). Cost: 1 point to acquire skill, then 1 point for +1.
Some Acquired Skills may require that characters have another Skill or Ability. In these cases, the required Skill or Ability is called a Prerequisite. For example, characters must have the Literacy Skill before they can have the Education Skill, or the Magic Talent Ability before they can have the Sorcery Skill.
Specialised Skills are an optional mechanism that allows characters to be especially good at performing one part of an Inherent or Acquired Skill. Examples include the exceptional archer who is no better than anyone else at using a sling or throwing a javelin, or the doctor who concentrates on optometry rather than general medical practice. In both cases, the character takes a Specialised Skill (Archery or Optometry) as well as the base (Inherent or Acquired) Skill (Aim or Medicine): the Specialised Skill's bonus is added to the base Skill modifier for Resolution Rolls whenever appropriate. Cost: 1 point for +2. The number of character points invested in a Specialised Skill cannot exceed the number of points invested in the base Skill.
Some Skills may be used any number of times in a Round. Others, however, may only be used three times at most. Characters with a Skill bonus of +1 or less may make only one action using their Skill modifier. Characters with a +2 bonus may act once at +2 or twice at +1/+1. Characters with a bonus of +3 or more may act up to three times, but may not take an action with a modifier of less than +1. For example, a character with a bonus of +6 cannot make three actions at +6/+0/+0 or +12/+0/-6: you cannot take an additional action at +0 or less. Once all three actions have been taken, or the bonus for the actions taken adds up to the character's total bonus, no further active actions may be taken, and all passive actions are at +0.
Characters cannot buy down a Skill bonus, but may take a Weakness and covert an Inherent Skill to an Acquired Skill. If the character then learns the Skill, they must buy off the Weakness before improving the Skill bonus.