Affinity

An Affinity represents your experience with, increased understanding of, and alignment with a specific conceptual force.
This grants an easier difficulty on checks for spells and skills related to the affinity.
Additionally, Skill Experience Cost to level up an Affinity Skill or Spell is reduced by an amount equal to 1 + the Affinity Level Milestone count. Class Experience Cost to Level Up equally affected for classes aligned with the Affinity.
Special Techniques and Traits can also synergize or alter effects based on Affinities.