Every ability, power, or spell belongs to one of seven magic schools which define what can be done to absorb, immunize against, or resist it. Your resistance against five of these schools are displayed in your character information. The magic schools are also used as damage types, but even abilities that don't cause damage have schools.
If you are a caster, and an opponent uses an interrupt effect such as , or on you while you're casting a spell, your cast will be interrupted, and you will be prevented from casting any spell in that school for a certain period time. It's good to know what schools your abilities are in so you can switch to another when this happens. It's fairly clear for mages (the school of the spell is the same as the tree it falls under) and warlocks (if it doesn't involve fire, it's Shadow). For other classes, it's not always clear. Fortunately, the tooltip of any damage spell will specify the type of damage it does. Some abilities belong to multi-schools, and behave a little differently.
Warriors are the only class that strictly deals only one damage type, that being Physical. Hunters and shaman have the most varied damage types, with both being able to deal Physical, Nature, and Fire damage, as well as Arcane and Shadow for hunters and Frost for shaman.
Not presented as magic to the user, but treated as a school by the game mechanics. All weapons except wands deal physical damage; the target can use Dodge to avoid the attack, a shield to Block it, the Parry skill to block it with a weapon, and Armor to resist some of the damage if all else fails. Damage taken is physical damage. Most warrior and rogue abilities are Physical. Death knight abilities obtained by spending talent points in the Blood Tree do physical damage. Armor penetration only ever applies to physical damage dealt.
Some physical abilities, like and , are treated like spells. These abilities have a chance to miss like all spells, which can be offset by Hit rating, but resistance to these abilities cannot be increased.
- See also: Category:Arcane spells
Most non-damaging magical hunter abilities, including , , , and are Arcane-based. , however, is a main source of direct damage, as is the druids' and . Also, the blood elf racial ability is Arcane-based. (Before patch 3.0.2, night elf priests could do Arcane damage with .)
The true masters of the Arcane, however, are mages. For mages, the Arcane school is primarily a utility line rather than a damage line. Any spell from a mage's Arcane ability category is of the Arcane school, including four spells that do damage (, , , ) and a very broad range of utility spells: Polymorphs, , , , , Teleports, Portals, , and Conjure Mana Gems, Food, and Water.
Hostile Arcane spells (including those that do no damage) can be resisted; there are items that increase one's Arcane resistance. Arcane is the only resistible magic school against which players cannot increase their Resistance via class abilities.
- See also: Category:Fire spells
Spells of the Fire school typically inflict damage, which can be direct damage and/or damage over time. Mages and warlocks use it as one of their primary source of damage, while shamans, hunter traps, and engineers also use the Fire school.
Many spells and environmental effects (such as lava) do Fire damage. The classes most associated with the ability to control fire are warlocks and mages. Fire is also one of the fundamental elements that shamans can manipulate with their Totems. In the same way, Warlocks deliver huge burst of Fire damage. Destruction warlocks are sometimes called "Firelocks". Hunters' and also deal Fire damage; similarly, explosives and damaging trinkets created by Engineers typically do Fire damage.
Like Arcane resistance, Fire resistance is a statistic that can be affected by spells and items.
- See also: Category:Frost spells
The Frost school is effective both for attack (doing damage) and defense (raising armor value). Frost spells often inflict snare or root effects, as well. Mages, shamans, death knights and the occasional hunter trap use the Frost school.
- See also: Category:Nature spells
The Nature school is usually used for nature based attacks, buffs, and curative spells. Nature damage can be direct damage (like lightning) or damage over time (like poison). This means that rogues (poison), shamans, druids, and hunters (stings) have access to Nature damage.
Acids, diseases, and poisons inflict Nature damage, and damage from lightning is also considered part of the Nature school. Shamans' and druids' healing spells are Nature spells, and other non-damaging spells such as and are in this school as well. Hunters' Stings and the 's viper poisons are Nature-based, as are their and abilities. Rogues' poisons are also Nature-based.
A Nature resistance statistic exists.
- See also: Category:Shadow spells
The opposite of Holy magic, Shadow is probably the most versatile school. Used by priests, warlocks, death knights, rogue and hunters () it contains a wide variety of spells. Apart from Direct Damage and Damage over Time spells, there are various utility spells, including Drains, Crowd Control spells, Debuffs, and even healing.
Shadow damage is dealt by dark spells such as those of the priest's Shadow abilities and most of the warlock's repertoire. The creation of a or and the summoning of demons are Shadow effects. Warlocks can also absorb Shadow damage with .
Shadow Resistance is the final resistance type.
- See also: Category:Holy spells
The Holy school is usually related to abilities which heal and aid living beings. There are also a few spells that do Holy damage, including and . Contrary to popular belief, Holy Magic does not deal additional damage to undead or demons.
It is not possible to resist Holy magic, giving it a slight advantage over other schools, but it does have a basic miss chance like all spells. This is of little value to players, and in PvE, NPCs' resistance is usually minimal anyway. However, NPC abilities that deal Holy damage can be significantly more harmful to a buffed raid group than damage of other schools.
Items and Buffs which give a bonus to all resistances do not include Holy resistance, but percentage-based damage-reduction abilities successfully reduce damage from Holy spells. Also, the and items will also absorb limited amounts of Holy damage.
Some abilities belong to multiple schools of magic. These multi-school abilities benefit from bonuses that affect any of their schools. They use the lowest resistance value among their schools, and they ignore absorption and immunity effects that apply to only some of their schools. Multi-schools were introduced with patch 4.0.1, although had served as a prototype of the effects of multi-schools since patch 3.0.2.
Interrupt effects are far less effective at locking players out of using multi-school spells. As long as any of the spell's schools is available, the player will still be able to cast the spell. This makes multi-school spells extremely hard to lock down, requiring the use of at least two consecutive interrupts (one for each school) in a very short space of time. This means that these abilities will almost always be available for players to cast when one of their schools is locked. In addition, some multi-school spells such as belong to schools that are not used by any of the class's other spells. When these spells are instant cast, this means that it is not possible for that spell to be locked down.