Wizards gain a spellbook, within which he stores the formulas for his spells. At level 0 and each level thereafter, his spellbook contains a number of Rank 1 spells equal to his Intelligence ability base.
- Whenever the wizard takes a short rest, he may prepare one spell of an appropriate rank from his spellbook for each of his available encounter spell uses, using an appropriate material component to infuse with the energy of his spell. He may cast each of those spells once during the next encounter.
- Whenever the wizard takes an extended rest, he may prepare one spell for each of his available daily spell slots from his spellbook, using an appropriate material component to infuse with the energy of his spell. He may cast each of those spells once during the next day.
Whenever a wizard gains a level, they may commit new spells to their spellbook. These must be of an effective Rank that they could cast as a daily spell, and the sum of all spell Ranks that they add to their spellbook each level is based on their level and their Intelligence ability base .
- Level 1 - 4: total Ranks equal to Intelligence ability base
- Level 5 - 8: total Ranks equal to Intelligence ability base + 1
- Level 9 - 10: total Ranks equal to Intelligence ability base + 2
These spells may come from any school of magic that the Wizard knows.
Additionally, if a Wizard finds an arcane spell scroll, they may expend this scroll instead of casting it to add the scroll's spell to their spellbook when they next gain a level, even if it is unavailable within the Wizard's known schools of magic. If the spell is not in one of the wizard's known schools, it counts as effectively one level higher, both when learning and when casting, until the wizard gains that spell's school of magic as one of his known schools. At-will spells from unknown schools become Rank 1 spells.