Each Art has its own "spark" level which determines how difficult it is to learn, and how strong the enemy has to be before you learn it. In general, the harder or more powerful the Art, the stronger the enemy needs to be in order to learn it. A character's Skill Level in a given weapon/Anima does not affect how easy it is to learn. Skill Levels only affect how powerful an Art is, and how likely it is to Spark new Arts or cause Status Effects. Arts are broken down into three separate categories: Weapon Arts, Spell Arts and Hybrid Arts.