Skill: Knowledge: Esoterica
Esoterica is the study and practice of magical things. Traditionally, this skill is called "Arcana" or "Occultism", while in this game the skill applies to all things Magical. This includes figuring out and determining how the various Spell Lists interact with the worlds they inhabit, as well as new Arcana that may arise.
Mechanically, Knowledge: Esoterica is a skill used to determine magical things, supplementing or outright replacing Spellcraft in many case and with many skill talents. Knowledge: Esoterica leans more on academics and potential, and is a skill any magical student can't live without.
Knowledge: Esoterica only uses INT / Intelligence by default. Knowledge: Esoterica is a Primary Skill, meaning it is a major skill that can only be gained by mechanics that grant proficiency. Additionally, it is a Knowledge Skill, which means it is a skill that requires a bit of input from the player and the GM to be used effectively, as well as a little bit of intuition on the player's side to use well.