In game terms, proficiency in a sphere is determined by one's rating in that sphere, judged on a scale of 0 (no skill) to 10 (mastery). All Hearthstones have been taught the rudiments, at least, of every sphere, and so have at least a 1, but other NPCs will most likely not have any proficiency in a sphere.
Each spell belongs to a particular sphere, and has a level rating within that sphere. A spell of a given level in a given sphere may only be learnt by someone of that level in that sphere. Some spells will require proficiency in more than one sphere, in which case both requirements must be fulfilled before that spell can be learnt. That spell still belongs only to one sphere; it merely has an additional pre-requisite.
Spells can be learnt by various means, most notably by reading spell books. Each book contains one spell. A character who lacks the required skill in the necessary spheres cannot learn the spell. However, a character will always be able to determine the name of the spell, its sphere, and a brief (and not necessarily accurate) description of its effects. Of course, all this assumes that the character can speak the language in which the book is written.
Casting spells often requires a certain degree of preparation, and therefore time. A Fast-Cast spell is a spell which can be cast with un-preparedness and haste (usually allowing it to be cast in combat), but which suffers in doing so. The detriment of Fast-Casting is different with every spell. There are also some spells which are actually designed for combative purposes; these, obviously, suffer no drawback for being cast quickly and during combat. They are designated by the word COMBAT.
A sphere is raised as per any other stat; every other level, a stat can be raised, and if you so choose, that stat could be a magical sphere. However, there is one stipend specific to spheres. Once a character has attained a level 5 proficiency in a sphere, for every level thereafter he must first attain a specific amount of knowledge before he can attain that level. This knowledge is expressed in terms of the spells he has already learned. Count up the level total of all of his spells of that sphere, a level 1 spell counting for 1 point, and so on in a rather obvious manner. This number is then his learning total for that sphere. To attain level 6 in a sphere, a learning total of 20 is required, and this is incremented by 20 for every level thereafter, so gaining the tenth level would required a total of 100 learning in that sphere. It is therefore very difficult to completely master a sphere.
Below will be covered, in slight detail, all the spheres, their alternate names, and all the spells which fall under them. They are written from the perspective of an learned outsider, though most spheres would of course not allow any outsider intimate knowledge of their higher level spells.
With every spell is written a description, one of the stats required to effect it (ROLL), and a difficulty (DIFF.). A spell may also have the identifier FAST-CAST or COMBAT attached to it; these are both covered above. If the spell is a Combat spell, it might well have a DMG identifier as well, which states the likely damage to be dealt. To determine if a spell succeeds, two statistics are combined and rolled against a certain difficulty. Every spell rolls its particular sphere + a stat given by ROLL, against the DIFF. listed. For more detail on rolling, see the Rolling Dice page.
Animism spells, particularly the lower-level ones, tend to require very little ritual or preparation; often, the only action necessary is direct interaction with the spirit in question.
Animism spells often deal with "binding" spirits. To bind a spirit is to metaphysically tether it to a place or thing. That place or thing then gains some of the characteristics of the spirit. An item with a spirit invested in to increase its power or effectiveness is called a fetish; for example, investing an arrow with a wind spirit might increase one's accuracy. Binding a powerful fire spirit to a forest location would make that location much more susceptible to forest fire.
Every binding has a "bind level". Bind level determines two things, firstly, the difficulty of breaking the bond between the spirit and its fetter, and secondly the length the bond will last under normal circumstances. Lowering a bind level to 0 will release the spirit automatically. The following is a chart displaying bind levels and corresponding length of time for which a spirit is bound:
| Bind | Time | Bind | Time |
|---|---|---|---|
| 1 | 15 min | 6 | 1 wk |
| 2 | 1 hr | 7 | 2 wk |
| 3 | 12 hr | 8 | 1 mth |
| 4 | 24 hr | 9 | 3 mth |
| 5 | 3 day | 10 | 1 yr |
The actual causative magic the Chaos magician employs is very minor. Most of his work goes into understanding the system which is to be manipulated. Therefore his work rarely requires much effort in the form of Stamina expenditure, but it is almost always difficult, and usually utilizes Intelligence or Perception.
There are no special rules related to Chaos magic, but many of the spells directly affect the way the game calculates the probability of an action's success; for more information on this, you should check out the page on dice.
Metempsychosis is helluva difficult to understand. I'll get around to explaining it eventually; likely, it will make use of a "mode" of some sort completely removed from Cairn Hill's regular game, "spirit mode" or something like that. Oh, well, we'll see.
I haven't worked it out fully quite yet, but certain objects will have a "connection rating" with certain people. Specific spells will require that you have objects with a minimum total "connection rating" to the target of the spell. Other spells, those dealing with the tie of similarity rather than the tie of experience, will instead require a certain type of object to work.
Related Links:
All Spheres § Spells § Animism § Cabbala § Chaos Magic § Metempsychosis § Necromancy § Sympathetic Magic