Niche D20One of the ways casting type is differentiated between casters is prepared and spontaneous magic. When first gaining the casting class feature the character may decide to be a spontaneous or prepared caster, once chosen all his casting classes are of this type of casting.
Spontaneous
A spontaneous caster learns talents and spells from their class or feats as they level and when casting in combat may cast any spell and apply talents as appropriate for that spell at the point of casting it.
A spontaneous caster’s magic comes from within rather than rigorous study and thus they do not require a spell source to pull their magic each day, though may still utilize an implement for their casting. The primary limitation of a spontaneous caster is that they are limited to their known spells and talents granted to them from class features, feats, or what was selected while leveling. Usually this means once selected a spontaneous caster’s talents cannot be changed once selected, unless otherwise specified.
Prepared
Prepared casters require more planning than spontaneous casters, but gain more flexibility in their access to various spells when compared to spontaneous casters.
Spell Source
A prepared caster usually draws their spells from an object (called their spell source), such as a spell tome containing their magics or a holy object that is used in religious ceremonies. A prepared caster’s spell source is usually defined as to the type of object based on their Casting Origin.
Each day after resting to regain spell points, a prepared caster must commune with this spell source to prepare their spells and talents for the day. This process usually requires a full hour of studying, prayer, meditation, or ritual and requires the caster to have access to their spell source.
When a caster first gains levels as a prepared caster they gain their spell source for free. Once a spell source is lost or destroyed it must be replaced by spending at least 100 gp on a suitable replacement item; though any spells and talents recorded within the spell source are lost when the spell source is lost. A character may write any talents currently prepared into a new spell source. A character may have more than one spell source, such as for having a backup, but may only prepare spells from a single spell source at a time.
While prepared casters still gain spells and talents from their class levels or feats, these do not automatically grant the caster access to a new spell or talent in their spell source (unless it is granting a specific spell or talent); instead these work as slots.
Adding New Spells and Talents Into A Spell Source
To obtain new spells or talents, a prepared caster must inscribe it (or perform a ritual that is appropriate for their spell source) into their spell source from a scroll or from another spell source. The caster may inscribe spells or talents he does not meet the prerequisites for (such as a minimum BCB), but still cannot prepare them unless he meets all the prerequisites for that spell or talent.
This process takes 1 hour to do and the caster must pay an amount of gold to cover expensive materials involved, which is calculated by the higher of their BCB or the required BCB of the spell multiplied by 10 gp (example: a 3 BCB caster would need to pay 30 gp to inscribe a new spell into his spell source).
Preparing Spells and Talents
Unlike a spontaneous caster, a prepared caster’s talents and spells granted by their class levels are treated as slots; these slots are empty until they are filled each day from your spell source. When preparing spells each day you empty out these slots and choose new spells and talents from your spell source.
Spells or talents selected must be able to fill the type of slot granted by the class’s talents, as most talent progressions will grant spells rather than one that can take a talent or spell. If a class or feature grants you a specific bonus spell or talent, that spell or talent is always considered to be prepared in its granted slot as long as you have access to your spell source and that slot cannot be used for another spell or talent. For example if a class grants the Grasping Vines spell as a bonus spell, you always have this spell available as it was granted as a bonus rather than as part of the class’s spell and talent progression.
Any prerequisites such as a required spell or talent must be met at the point of preparation. For example Tripping Vines talent cannot be prepared unless you also prepare (or have available) the Grasping Vines spell.