In several descriptions of the class it says they get spellbok. My question is why? in The pnp they do not get or need one and the appeal of the class was no need of a spellbook or no need of infusions known. They can cast any and every infusion on their list and their infusion the most limited of all casters (before the Warlock) and their casting of infusions per-day is also limited, which they do not need a spellbook. It goes against the flavor of class if they have a spellbook. They do prepare their infusions for the day though which could be similar to a cleric or Favored Soul type casting for DDO version.