The limited ammunition idea coincided neatly with the depiction of magic in the novels of Jack Vance, and thus was coined the term Vancian magic. In his novels, wizards had to study their spellbooks to prepare spells. They could only memorise a certain number of spells at once, and once they had been cast, the spells faded from memory until the wizard could take time to study thier spellbooks once again. When smaller-scale roleplaying games developed - where each player had a single character unit instead of an entire army - the Vancian system was retained.
There are two main types of magic in D&D and Pathfinder: arcane and divine. Arcane magic is used by sorcerers, wizards and bards, stemming from the caster having a connection to the essence of magic itself. Divine magic is used by clerics, paladins, druids and rangers, and is magic granted by devotion to a deity or some sort of ideal or concept, like nature. Later versions of D&D have split off the nature classes like druid and ranger, and classed their magic as a third kind, 'primal'. Pathfinder still views them as divine casters, but has also added a third kind of magic - psychic. I have included more info on each of Pathfinder's magic categories below.
Arcane Magic
Wizard, Witch, Sorcerer, Magus, Bard
All arcane spells have two main components, called verbal and somatic. Think of the spells in the Harry Potter novels - each one has words that must be said (verbal), and a gesture that one must do with the wand (somatic). You don't need a wand in Pathfinder, however. These two components mean that it can be easy to shut down wizards - if they are gagged, put into a zone of silence, or have their hands tied up, they will be unable to cast spells. Arcane spellcasters are limited in what armour they can wear, as any armour besides the expensive mithral chain shirt will interfere with their somatic component. (And yes, that is very much a Hobbit reference.)
The wizards of Pathfinder, like the old tabletop wizards, still have to walk around carrying spellbooks filled with their spells. They must spend time consulting them at the beginning of each day, in order to prepare a number of spells up to the maximum number they can cast each day. These days, they are usually referred to as prepared spellcasters. The wizard class is extremely powerful, with access to a wide variety of spells for every occasion, but the preparation rules limit them significantly, as they can easily get stuck with prepared spells that are useless for the current situation.
Many people greatly dislike the preparation rules. The sorcerer class was made as an attempt to alleviate the problems with it. Sorcerers are based on a different sort of literary magic user - one born with inherent magical abilities, who does not need to learn magic. Sorcerers are called spontaneous spellcasters and don't have spell books. They don't need to prepare, but can choose to cast any spell they know, as long as they don't exceed the maximum number of spells they cast per day. They are, however, limited in spell knowledge - they only know a small number of spells compared to wizards.
Witches are prepared arcane casters, but have a significantly different spell list to wizards and sorcerers, a list that included a lot of spells previously only castable by clerics and druids. Witches cast these formerly divine-only spells as arcane spells, thus blurring the lines between arcane and divine magic.
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| Illustration by Wayne Reynolds |
Divine Magic
Cleric, Oracle, Inquisitor, Paladin; Druid, Shaman, Ranger
Compared to arcane spellcasters, divine casters have it easy. They don't need spellbooks, can use armour without worrying about spell failure, and prepared divine casters like clerics and druids know every divine spell that it is possible for them to cast. Need a niche spell to pull off a clever strategy? If you have enough time, they can just prepare it and you're good. They even have better health and attack bonuses than the arcane classes! (Prepared divine casters, like oracles, do have a limited amount of known spells, like sorcerers.)
Much of their magic still uses verbal and somatic components, making them susceptible to the same things that shut down arcane spellcasters. In addition, their magic requires a divine focus - a holy symbol for the more religious classes, or a sprig of mistletoe for those of a natural persuasion. Deprive them of their focus, and they can't cast spells. They are easy and cheap to replace, unless you want them to be really fancy.
I personally think it is silly that the three nature-focused spellcasters are lumped in with the divine casters, and in my games I usually make it hard for each group to recognise spells cast by the other - like how arcane and divine spellcasters struggle to recognise each other's spells.
Mechanically, there's not a lot of difference between arcane, divine and nature-divine magic, it's more of a story thing that needs to be played up by the GM and players for it to actually be relevant. Psychic magic, on the other hand...
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| Illustration by Tomasz Chistowski |
Psychic Magic
Psychic, Occultist, Spiritualist
Psychic magic is both elegant and problematic. D&D's psychic classes had spell-like powers that worked completely differently to other spellcasters. Pathfinder decided that they didn't want people to have to learn a whole new system of 'spellcasting'. So they decided that psychic magic would work just like arcane magic, with a two key differences.
Instead of the normal components, psychic magic uses emotion and thought components. This means that most of the usual ways to stop spellcasters, like silence and binding their hands, doesn't work on them. But, anything that messes with their emotions - like a fear spell - will shut off their ability to cast. The intense thought required also means they have difficulty casting defensively, making melee combat even less desirable for them than it is for wizards.
Secondly, all psychic classes use spontaneous casting. Prepared casting for psychic magic does not exist.
The problem with psychic magic being slotted into the game this way is that, despite the fact that you can always tell when a spellcaster is casting a spell, the game doesn't explain how this works for psychic magic. Wizards, clerics and druids visibly move their hands and mutter incantations, but psychics do not. You can't see the psychic components. So we have to come up with our own explanation. Perhaps their eyes glow blue, or mystical sigils appear in the air around them, or you just get this nagging feeling that the guy in the corner is trying to read your mind. It's not hard to come up with something fun for it, but it makes for a lot of initial confusion when you are trying to work out how to play one, as it isn't brought up at all, and you have to go searching through forums to find an official answer, that yes, you can always tell.
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| Illustration by Wayne Reynolds |
Alchemy
Alchemist, Investigator
Alchemy is actually just arcane magic. However, the mechanics used by alchemists and investigators (a class inspired by Arkham Horror) circumvent many of the limitations of arcane magic. They actually 'cast' all their spells at the beginning of the day, by creating extracts, which basically act as potions that they can later drink. While preparing extracts requires components, drinking an extract does not, and has no risk of spell failure. Alchemists and investigators can basically cheat their way around the restrictions by only putting on their armour after preparing extracts, and don't care about Silence. They are not without drawback - that their spell list is a lot more limited than wizards or sorcerers, mostly defensive spells that affect only them, and lack the three highest spell levels.
In all other ways, alchemists and investigators mirror wizards - they have a formula book with all their extracts written down, and they prepare them in advance.
