Almost every spell belongs to one of eight schools of magic. A school of magic is a group of related spells that work in similar ways. A small number of spells are universal, belonging to no school.
Abjurations are protective spells. They create physical or magical barriers, negate magical or physical abilities, harm trespassers, or even banish the subject to another plane of existence.
If more than one abjuration spell is active within 10 feet of another for 24 hours or more, the magical fields interfere with each other and create barely visible energy fluctuations. The DC to find such spells with the Search skill drops by 4.
If an abjuration creates a barrier that keeps certain types of creatures at bay, the barrier cannot be used to push away those creatures. If the character forces the barrier against such a creature, the character feels a discernible pressure against the barrier. If the character continues to apply pressure, the character breaks the spell.
Conjurations bring manifestations of objects, creatures, or some form of energy to the character (summoning), actually transport creatures from another plane of existence to the character's plane (calling), heal (healing), or create such objects or effects on the spot (creation). Creatures the character conjures usually, but not always, obey the character's commands.
A creature or object brought into being or transported to the character's location by a conjuration spell cannot appear inside another creature or object, nor can it appear floating in an empty space. It must arrive in an open location on a surface capable of supporting it. The creature or object must appear within the spell's range, but it does not have to remain within the range.
Calling: The spell fully transports a creature from another plane to the plane the character is on. The spell grants the creature the one-time ability to return to its plane of origin, although the spell may limit the circumstances under which this is possible. Creatures who are called actually die when they are killed; they do not disappear and reform, as do those brought by a summoning spell (see below). The duration of a calling spell is instantaneous, which means that the called creature can't be dispelled.
Spells that call powerful extraplanar creatures are most useful when the conjurer has a magical trap to hold the summoned creature. The simplest type of trap is a magic circle spell (magic circle against chaos, magic circle against evil, etc.). When focused inward, a magic circle spell binds a called creature for a maximum of 24 hours per caster level, provided that the character casts the spell that calls the creature within 1 round of casting the magic circle. However, if the circle laid down in the process of spellcasting is broken, the effect immediately ends. The trapped creature can do nothing that disturbs the circle, directly or indirectly, but other creatures can. If the called creature has spell resistance, it can test the trap once a day. If the character fails to overcome the spell resistance, the creature breaks free, destroying the circle. A creature capable of any form of dimensional travel can simply leave the circle through that means. The character can prevent the creature's extradimensional escape by casting a dimensional anchor spell on it, but the character must cast the spell before the creature acts. If successful, the anchor effect lasts as long as the magic circle does. The creature cannot reach across the magic circle, but its ranged attacks (ranged weapons, spells, magical abilities, etc.) can. The creature can attack any target it can reach with its ranged attacks except for the circle itself.
The character can use a special diagram to make the trap more secure. Drawing the diagram by hand takes 10 minutes and requires a Spellcraft check (DC 20). The DM makes this check secretly. If the check fails, the diagram is ineffective. The character can take 10 when drawing the diagram if the character is under no particular time pressure to complete the task. This also takes 10 full minutes. If time is no factor at all, and the character devotes 3 hours and 20 minutes to the task, the character can take 20. A successful diagram allows the character to cast a dimensional anchor spell on the trap during the round before casting any summoning spell. The anchor holds any called creatures in the diagram for 24 hours per caster level. A creature cannot use its spell resistance against a trap prepared with a diagram, and none of its abilities or attacks can cross the diagram. If the creature tries a Charisma check to break free of the trap, the DC increases by 5. The creature is immediately released if anything disturbs the diagram—even a straw laid across it. However, the creature cannot disturb the diagram itself either directly or indirectly, as noted above.
Creation: The spell manipulates matter to create an object or creature in the place the spellcaster designates (subject to the limits noted above for conjurations). If the spell has a duration other than instantaneous, magic holds the creation together, and when the spell ends or is dispelled, the conjured creature or object vanishes without a trace. If the spell has an instantaneous duration, the created object or creature is merely assembled through magic. It lasts indefinitely and does not depend on magic for its existence.
Healing: Certain divine conjurations heal creatures or even bring them back to life. These include cure spells, which good clerics can cast spontaneously.
Summoning: The spell instantly brings a creature or object to a place the character designates. When the spell ends or is dispelled, a summoned creature is instantly sent back to where it came from, but a summoned object is not sent back unless the spell description specifically indicates this. A summoned creature also goes away if it is killed or dropped to 0 hit points. It is not really dead. It takes 24 hours for the creature to reform, during which time it can't be summoned again.
When the spell that summoned a creature ends and the creature disappears, all the spells it has cast end (if they haven't already). A summoned creature cannot use any innate summoning abilities it may have, and it refuses to cast any spells or use any spell-like abilities that would cost it XP.
Divination spells enable the character to learn secrets long forgotten, to predict the future, to find hidden things, and to foil deceptive spells.
Many divination spells have cone-shaped areas. These move with the character and extend in the direction the character looks. The cone defines the area that the character can sweep each round. If the character studies the same area for multiple rounds, the character can often gain additional information, as noted in the descriptive text for the spell.
Enchantment spells affect the minds of others, influencing or controlling their behavior.
All enchantments are mind-affecting spells. Two types of enchantment spells grant the character influence over a subject creature:
Charm: The spell changes the way the subject views the character,
typically making the subject sees the character as a good friend.
Compulsion: The spell forces the subject to act in some manner or changes the
way her mind works. Some spells determine the subject's actions (or the effects
on the subject), some allow the character to determine the subject's actions when
the character casts the spell, and others give the character ongoing control over
the subject.
Evocation spells manipulate energy or tap an unseen source of power to produce a desired end. In effect, they create something out of nothing. Many of these spells produce spectacular effects, and evocation spells can deal large amounts of damage.
Illusion spells deceive the senses or minds of others. They cause people to see things that are not there, not see things that are there, hear phantom noises, or remember things that never happened. Illusions come in five types: figments, glamers, patterns, phantasms, and shadows.
Figment: A figment spell creates a false sensation. Those who perceive the figment perceive the same thing, not their own slightly different versions of the figment. (It is not a personalized mental impression.) Figments cannot make something seem to be something else. A figment that includes audible effects cannot duplicate intelligible speech unless the spell description specifically says it can. If intelligible speech is possible, it must be in a language the character can speak. If the character tries to duplicate a language the character cannot speak, the image produces gibberish. Likewise, the character cannot make a visual copy of something unless the character knows what it looks like.
Because figments and glamers (see below) are unreal, they cannot produce real effects the way that other types of illusions can. They cannot cause damage to objects or creatures, support weight, provide nutrition, illuminate darkness, or provide protection from the elements. Consequently, these spells are useful for confounding or delaying foes, but useless for attacking them directly.
Glamer: A glamer spell changes a subject's sensory qualities, making it look, feel, taste, smell, or sound like something else, or even seem to disappear.
Pattern: Like a figment, a pattern spell creates an image that others can see, but a pattern also affects the minds of those who see it or are caught in it. All patterns are mind-affecting spells.
Phantasm: A phantasm spell creates a mental image that usually only the caster and the subject (or subjects) of the spell can perceive. This impression is totally in the minds of the subjects. It is a personalized mental impression. (It's all in their heads and not a fake picture or something that they actually see.) Third parties viewing or studying the scene don't notice the phantasm at all. All phantasms are mind-affecting spells.
Shadow: A shadow spell creates something that is partially real (quasi-real). The caster weaves it from extradimensional energies. Such illusions can have real effects. If a creature takes damage from a shadow illusion, that damage is real.
Saving Throws and Illusions (Disbelief): Creatures encountering an illusion effect usually do not receive saving throws to recognize it as illusory until they study it carefully or interact with it in some fashion.
A successful saving throw against an illusion reveals it to be false, but a figment or phantasm remains as a translucent outline.
A failed saving throw indicates that a character fails to notice something is amiss. A character faced with incontrovertible proof that an illusion isn't real needs no saving throw. If any viewer successfully disbelieves an illusion and communicates this fact to other viewers, each such viewer gains a saving throw with a +4 bonus.
Necromancy spells manipulate the power of death. Spells involving undead creatures make up a large part of this school.
Transmutation spells change the properties of some creature, thing, or condition. A transmutation usually changes only one property at a time, but it can be any property.