Arcane Spellcasting
Wizards, sorcerers, and bards cast arcane spells. Arcane spells involve the direct manipulation of mystic energies. These manipulations require natural talent (in the case of sorcerers), long study (in the case of wizards), or both (in the case of bards.) Compared to divine spells, arcane spells are more likely to produce dramatic results such as flight, explosions, or transformations. What arcane spells do poorly is heal wounds.
Preparing Wizard Spells
Before setting out on an adventure with her companions, Mialee (at 1st level) pores over her spellbook and prepares two 1st-level spells (one for being a 1st-level wizard and an additional one as her 1st-level bonus spell for Intelligence 15) and three 0-level spells. (Arcane spellcasters often call their 0-level spells "cantrips.") From the spells in her spellbook, she chooses charm person, sleep, detect magic (twice), and light. While traveling, she and her party are attacked by gnoll raiders, and she casts her sleep spell. After she and her companions have dispatched the gnolls, she casts detect magic to see whether any of the gnolls' items are enchanted. (They're not.) The party then camps for the night in the wilderness. Come morning, Mialee can once again prepare spells from her spellbook. She already has charm person, detect magic (once), and light prepared from the day before. She chooses to abandon her light spell and then prepare sleep, detect magic, and ghost sound. It takes her a little over half an hour to prepare these spells because they represent a little over half of her daily capacity.
A wizard's level limits the number of spells she can prepare and cast. A wizard's high Intelligence score might allow her to prepare a few extra spells. She can prepare the same spell more than once, but each preparation counts as one spell toward her daily limit. Preparing arcane spells is an arduous mental task. To do so, the wizard must have an Intelligence score of at least 10 plus the spell's level.
Rest: To prepare her daily spells, a wizard must have a clear mind. To clear her mind, the wizard must first sleep for 8 hours. The character does not have to slumber for every minute of the time, but she must refrain from movement, combat, spellcasting, skill use, conversation, or any other fairly demanding physical or mental task during the rest period. If the wizard's rest is interrupted, each interruption adds 1 hour to the total amount of time she has to rest in order to clear her mind, and the wizard must have at least hour of rest immediately prior to preparing her spells. If the character does not need to sleep for some reason, she still must have 8 hours of restful calm before preparing any spells. For example, elven wizards need 8 hours of rest to clear their minds even though they need only 4 hours of trance to refresh their bodies (so they could trance for 4 hours and rest for 4 hours and then prepare spells).
Recent Casting Limit/Rest Interruptions: If a wizard has cast spells recently, the drain on her resources reduces her capacity to prepare new spells. When she prepares spells for the coming day, all spells she has cast within the last 8 hours count against her daily limit. If Mialee can normally cast two 1st-level spells a day, but she had to cast magic missile during the night, she can only prepare one 1st-level spell the next day.
Preparation Environment: To prepare any spell, the wizard must have enough peace, quiet, and comfort to allow for proper concentration. The wizard's surroundings need not be luxurious, but they must be free from overt distractions, such as combat raging nearby or other loud noises. Exposure to inclement weather prevent the necessary concentration, as does any injury or failed saving throw the character might suffer while studying. Wizards also must have access to their spellbooks to study from and sufficient light to read them by. One major exception: A wizard can prepare a read magic spell even without a spellbook. A great portion of a wizard's initial training goes into mastering this minor but vital feat of magic.
Spell Preparation Time: After resting, a wizard must study her spellbook to prepare any spells that day. If the character wants to prepare all her spells, the process takes 1 hour. Preparing a smaller portion of her daily capacity takes a proportionally smaller amount of time, but always at least 15 minutes, the minimum time required to achieve the proper mental state.
Spell Selection and Preparation: Until she prepares spells from her spellbook, the only spells a wizard has available to cast are the ones that she already had prepared from the previous day and has not yet used. During the study period, a wizard chooses which spells to prepare. The act of preparing a spell is actually the first step in casting it. A spell is designed in such a way that it has an interruption point near its end. This allows a wizard to cast most of the spell ahead of time and finish the spell when it's needed, even if the character is under considerable pressure. The wizard's spellbook serves as a guide to the mental exercises the wizard must perform to create the spell's effect. If a wizard already has spells prepared (from the previous day) that she has not cast, she can abandon some or all of them to make room for new spells.
When preparing spells for the day, the wizard can leave some spell slots open. Later during that day, the wizard can repeat the preparation process as often as she likes, time and circumstances permitting. During these extra sessions of preparation, a wizard can fill these unused spell slots. She cannot, however, abandon a previously prepared spell to replace it with another one or fill a slot that is empty because she has cast a spell in the meantime. That sort of preparation requires a mind fresh from rest. Like the first session of the day, this preparation takes at least 15 minutes, and it take longer if the wizard prepares more than one-quarter of her spells.
Prepared Spell Retention: Once a wizard prepares a spell, it remains in her mind as a nearly cast spell until she uses the prescribed components to complete and trigger it (or until she abandons it). Upon casting, the spell's energy is expended and purged from the character, leaving her feeling a little tired. Certain other events, such as the effects of magic items or special attacks from monsters, can wipe a prepared spell from a character's mind.
Death and Prepared Spell Retention: If the character dies, all spells stored in her mind are wiped away. Potent magic (such as raise dead, resurrection, or true resurrection) can recover the lost energy when it recovers the character.
Arcane Magical Writings
To record an arcane spell in written form, a character uses complex notation that describes the magical forces involved in the spell. The notation constitutes a universal arcane language that wizards have discovered, not invented. The writer uses the same system no matter what her native language or culture, However, each character uses the system in her own way. Another person's magical writing remains incomprehensible to even the most powerful wizard until she takes time to study and decipher it.
To decipher an arcane magical writing (such as a single spell in written form in another's spellbook or on a scroll), a character must make a successful Spellcraft check (DC 20 + the spell's level). If the skill check fails, the character cannot attempt to read that particular spell until the next day. A read magic spell automatically deciphers a magical writing without a skill check. If the person who created the magical writing is on hand to help the reader, success is also automatic.
Once a character deciphers a particular magical writing, she does not need to decipher it again. Deciphering a magical writing allows the reader to identify the spell and gives some idea of its effects (as explained in the spell description), If the magical writing was a scroll and the reader can cast arcane spells, she can attempt to use the scroll (See scrolls).
Wizard Spells and Borrowed Spellbooks
A wizard can use a borrowed spellbook to prepare a spell she already knows and has recorded in her own spellbook, but preparation success is not assured. First, the wizard must decipher the writing in the book (see Arcane Magical Writings, above). Once a spell from another spellcaster's book is deciphered, the reader must make a successful Spellcraft check (DC 15 + spell's level) to prepare the spell. If the check succeeds, the wizard can prepare the spell. She must repeat the check to prepare the spell again, no natter how many times she has prepared the spell before. If the check fails, she cannot try to prepare the spell from the same source again until the next day (However, as explained above, she does not need to repeat a check to decipher the writing.)
Adding Spells to a Wizard's Spellbook
Wizards can add new spells to their spellbooks through several methods. If a wizard has chosen to specialize in a school of magic, she can learn spells only from schools she can cast.
Spells Gained at a New Level: Wizards perform a certain amount of spell research between adventures. Each time a wizard achieves a new level, she gains two spells of her choice to add to her spellbook. These spells represent the results of her research.
The two free spells must be of levels the wizard can cast. If she has chosen to specialize in a school of magic, one of the two free spells must be the from the wizard's specialty school.
Spells Copied from Another's Spellbook or a Scroll: A wizard can also add spells to her book whenever she encounters a new spell on a magic scroll or in another wizard's spellbook. No matter what the spell's source, the character must first decipher the magical writing (see Arcane Magical Writings). Next, the wizard must spend a day studying the spell. At the end of the day, the character must make a Spellcraft check (DC 15 + spell's level). A wizard who has specialized in a school of spells gains a +2 bonus to the check if the new spell is from her specialty school. She cannot, however, learn any spells from her prohibited schools.
If the check succeeds, the wizard understands the spell and can copy it into her spellbook (see Writing a New Spell into a Spellbook, below). The process leaves a spellbook that was copied from unharmed, but a spell successfully copied from a magic scroll disappears from the scroll.
If the check fails, the wizard cannot understand the spell and cannot attempt to learn it again even if she studies it from another source until she gains another rank in Spellcraft. If the check fails, the character cannot copy the spell from another's spellbook, and the spell does not vanish from the scroll.
Independent Research: A wizard also can research a spell independently, duplicating an existing spell or creating an entirely new one. The DUNGEON MASTER's Guide has information on this topic.
Writing a New Spell into a Spellbook
Once a wizard understands a new spell, she can record it into her spellbook.
Time: The process requires 1 day plus 1 additional day per spell level. Zero-level spells require 1 day.
Space in the Spellbook: A spell takes up 2 pages of the spellbook per spell level (so a 2nd-level spell takes 4 pages, a 5th-level spell takes to pages, and so forth). A 0-level spell (cantrip) takes but a single page. A spellbook has 100 pages.
Materials and Costs: Materials for writing the spell (special quills, inks, and other supplies) cost 100 gp per page.
Note that a wizard does not have to pay these costs in time or gold for the spells she gains for free at each new level. The wizard adds these to her spellbook as part of her ongoing research.
Replacing and Copying Spellbooks
A wizard can use the procedure for learning a spell to reconstruct a lost spellbook. If she already has a particular spell prepared, she can write it directly into a new book at a cost of 100 gp per page (as noted in Writing a New Spell into a Spellbook). The process wipes the prepared spell from her mind, just as casting it would. If she does not have the spell prepared, she can prepare it from a borrowed spellbook and then write it into a new book.
Duplicating an existing spellbook uses the same procedure as replacing it, except that the task is much easier. The time requirement and cost per page are halved.
Sorcerers And Bards
Sorcerers and bards cast arcane spells, but they do not have spellbooks and do not prepare spells. A sorcerer's or bard's level limits the number of spells he can cast. A sorcerer's or bard's high Charisma score might allow him to cast a few extra spells. Members of either class must have a Charisma score of at least 10 + a spell's level to cast the spell.
Daily Readying of Spells: Each day, sorcerers and bards must focus their minds on the task of casting their spells. A sorcerer or bard needs 8 hours of rest (just like a wizard), after which he spends 15 minutes concentrating. A bard must sing or play an instrument of some kind while concentrating. During this period, the sorcerer or bard readies his mind to cast his daily allotment of spells. Without such a period to refresh himself, the character does not regain the spell slots he used up the day before.
For example, at 7th level, Devis the bard can cast one 3rd-level spell (a bonus spell due to his 16 Charisma). If he casts his 3rd-level spell, he can't use it again until the next day - after he readies his spells for the day
Recent Casting Limit: As with wizards, any spells cast within the last 8 hours count against the sorcerer's or bard's daily limit.
Adding Spells to a Sorcerer's or Bard's Repertoire: Sorcerers and bards gain spells each time they attain new experience levels and never gain spells any other way. When you gain a new level, consult Bard Spells Known or Sorcerer spells Known to learn how many spells from the appropriate spell list, Sorcerer, or Bard. With the DM's permission, sorcerers and bards can also select the spells they gain from new and unusual spells that they have gained some understanding of.
For instance, when Hennet the sorcerer becomes 2nd level, he gains an additional 0-level spell. He can pick that spell from the 0-level spells on the sorcerer and wizard spell list, or he might have learned an unusual spell from an arcane scroll or spellbook.
Arcane Spells And Armor
Wizards and sorcerers do not know how to wear armor effectively. They can wear armor anyway (though they'll be clumsy in it), and they can gain training in the proper use of armor (with the various Armor proficiency feats - light, medium, and heavy - and the Shield Proficiency feat) or multiclass to add a class that grants them armor use. By contrast, bards do know how to wear light and medium armor effectively. However, they too wear heavier armor ineffectively and must either learn to wear heavier armor via the feat Armor Proficiency (heavy) or add a class (such as fighter) that grants them such Armor Proficiency as a class feature. Even if a wizard, sorcerer, or bard is wearing armor with which he or she is proficient, however, it might still interfere with his or her spell.
Characters have a difficult time casting most arcane spoils while wearing armor. The armor restricts the complicated gestures that they must make while casting any spell that has a somatic component (most do). To find the chance of arcane spell failure for a wizard, sorcerer, or bard wearing different types of armor, see Armor.
If a spell doesn't have a somatic component, arcane spellcasters can cast it with no problem while wearing armor. Such spells can also be cast even if the caster's hands are bound or if he or she is being grappled (although Concentration checks still apply). Also, the metamagic feat Still Spell allows a spellcaster to prepare or cast a spell at one level higher than normal without the somatic component, which is a way of casting a spell while wearing armor without risking the chance of arcane spell failure.
School Specialization
A school is one of eight groupings of spells, each defined by a common theme, such as illusion or necromancy. A wizard may specialize in one school of magic (see below). Specialization allows a wizard to cast extra spells from the chosen school, but the wizard then never learns to cast spells from one or more other schools. Essentially, the wizard gains exceptional mastery over a single school by neglecting the study of other schools. The more difficult a school is to master, the more one must give up in order to specialize in it. Some schools only require that a specialist give up one other school, while others might require the giving up of two or three. Spells of the school or schools that the specialist gives up are not available to her, and she can't even cast such spells from scrolls or wands. The wizard must choose whether to specialize and how at 1st level. She may not change her specialization later. The specialist can prepare one additional spell (of the school selected as a specialty) per spell level each day. The specialist gains a +2 bonus to Spellcraft checks to learn the spells of her chosen school (see Adding Spells to a Wizard's Spellbook).
The eight schools of arcane magic are Abjuration, Conjuration, Divination, Enchantment, Evocation, Illusion, Necromancy, and Transmutation. Spells that do not fall into any of these schools are called universal spoils.
Abjuration: Spells that protect, block, or banish. An Abjuration specialist is called an abjurer. To become an abjurer, a wizard must select her prohibited school or schools from the following choices: (1) either Conjuration, Enchantment, Evocation, Illusion, or Transmutation; or (2) both Divination and Necromancy.
Conjuration: Spoils that bring creatures or materials to the caster. A Conjuration specialist is called a conjurer. To become a conjurer, a wizard must select her prohibited school or schools from one of the following choices: (1) Evocation; (2) any two of the following three schools: Abjuration, Enchantment, and Illusion; (3) Transmutation, or (4) any three schools.
Divination: Spells that reveal information. A Divination specialist is called a diviner. To become a diviner, a wizard must select any other single school as her prohibited school.
Enchantment: Spells that imbue the recipient with some property or grant the caster power over another being. An Enchantment specialist is called an enchanter. To become an enchanter, a wizard must select her prohibited school or schools from the following choices: (1) either Abjuration, Conjuration, Evocation, Illusion, or Transmutation; or (2) both Divination and Necromancy.
Evocation: Spells that manipulate energy or create something from nothing. An Evocation specialist is called an evoker. To become an evoker, a wizard must select her prohibited school or schools from one of the following choices: (1) Conjuration; (2) any two of the following three schools: Abjuration, Enchantment, and Illusion; (3) Transmutation; or (4) any three schools.
Illusion: Spells that alter perception or create false images. An Illusion specialist is called an illusionist. To become an illusionist, a wizard must select her prohibited school or schools from the following choices: (1) either Abjuration, Conjuration, Enchantment, Evocation, or Transmutation; or (2) both Divination and Necromancy.
Necromancy: Spells that manipulate, create, or destroy life or life force. A Necromancy specialist is called a necromancer. To become a necromancer, a wizard must select any other single school as her prohibited school.
Transmutation: Spells that transform the recipient physically or change its properties in a more subtle way. A Transmutation specialist is called a transmuter. To become a transmuter, a wizard must select her prohibited school or schools from one of the following choices: (1) Conjuration; (2) Evocation; (2) any two of the following three schools: Abjuration, Enchantment, and illusion; or (4) any three schools.
Universal: Not a school, but a category for spells all wizards can learn. A wizard cannot select universal as a specialty school or as a school to which she does not have access.
Also see Schools of Magic and Subschools