The research should cost at least 1,000 gp per spell level (or even more for particularly exotic spells) and require both the Spellcraft skill and a Knowledge skill appropriate to the researcher’s class. Wizards and bards use Knowledge (arcana), sorcerers use a Knowledge skill appropriate to their heritage (usually arcana, nature, or planes), druids and rangers use the Knowledge (nature) skill, and clerics and paladins use Knowledge (religion). The actual research process varies by the type of spell, often involving magical experimentation, the purchase and study of moldy scrolls and grimoires, contact with powerful magical beings or outsiders, and extensive meditation or rituals.
For every two weeks of research, the caster makes separate Knowledge and Spellcraft checks against a DC of 20 plus twice the level of the spell being researched, modified according to Table: Spell Research Modifiers. To successfully research the spell, the caster must succeed at both checks. Failure indicates two weeks were wasted. Spells of 4th-6th level requires 4 weeks of successful research, while spells of 7th-9th level require 8 weeks per level. The researcher may employ up to two assistants in the research process to assist on the skill checks using the aid another action. All researchers must have the minimum relevant spellcasting ability score that would allow them to be able to cast the spell, therefore, a 4th-level spell requires researcher and assistants with a spellcasting ability score of 14.
It is not possible to take 10 or take 20 on these checks.
Table: Spell Research Modifiers
Caster already knows a similar spell
-2 circumstance modifier
Per material component required
-2 (maximum -6) circumstance modifier
-2 to -5 based on cost and rarity circumstance modifier
No verbal component
+10 circumstance modifier
No somatic component
+5 circumstance modifier
Additional research materials
-1 per 100 gp per spell level (maximum +5)
Researching spell from another spell list
-2 circumstance modifier (cannot be combined with 'Caster already knows a similar spell') requires a copy of the spell.
The researcher must have access to a laboratory or sanctuary relevant to their spellcasting ability.
A Basic Laboratory can be rented at a price of 250 gp/week. Paying 500 gp/week for better services, materials, and equipment provides a +2 circumstance bonus on Spellcraft checks made to determine whether a new spell is viable.
A Fancy Laboratory can be rented for 750 gp/week, and a single spellcaster using this laboratory and having its resources all to himself receives a +4 circumstance bonus on Spellcraft checks made to determine whether a new spell is viable. Alternatively, up to four spellcasters can share this space at the same time and gain a +2 circumstance bonus on such checks.
The price of hiring an assistant's services is equal to that of hiring spellcasting services, where 'caster level' becomes 'Spellcraft Check Modifier' per two weeks of research.
Spell research before character creation is still resolved with dice rolls; the researched spell must be presented to the DM for approval and then success determined in the relevant thread.
In game, it is possible to mitigate costs; use another character's library or the sanctuary of a friendly and fellow worshiper, however the costs of materials and research materials cannot be reduced, though where the funds come from does not truly matter.