All magic users have Paths - directions that their spells naturally move in. For example, Daisy Archanis has a bent towards teleportation. This encompasses spells like Teleport Self, Teleport Others, and Teleport Objects (Daisy has only shown any definitive knowledge of the first). She could, in theory, learn any of these spell nodes with only mild difficulty and effort (ie, spending the normal cost for a node).
Most Paths may be summed up in a word, or short phrase. "Destruction Through Analysis" would be a path that creates spells in which a weakness is discerned, and then exploited. It would allow for spells in the Sensory category, to find weaknesses, possible a Mind spell to enhance cognition, and material destruction spells that take advantage of this analysis. "Matter Destruction," as a Path, would be more limited, having only the destructive aspect, but would not require the analysis aspect to function - they'd simply blow up anything they'd like (assuming they're powerful enough to do so). Both are effective Paths, but have very different play styles.
In Game Assignment Edit
Before a game begins, all magic users should work with their GM to find a suitable Path for their characters, and set some guidance on what the Path can and cannot do. It is strongly recommend that a player also consider what sort of character might have that sort of Path, and how they feel about their magical abilities. Sterlings that Shatter and gain some casting ability should either have a similar discussion with the GM, or the GM should assign an appropriate starting Path.
With a great deal of training, additional Paths may be unlocked, which vary from this main path in some degree. Spells may then be learned along this new path, or be evaluated between the two Paths. For example, a being with both an Electric Path and a Heat Path could use a spell node that converts one to the other, or manifests both simultaneously. These linked nodes are referred to Bridge nodes.
A single character may not have more Paths than they have ranks on the Soul Tree, and they must be paid for at the current Soul Tree Level's cost. They also come after in game effort - at the very least, a character must be actively pursuing it in their off hours, and the player should be making an effort to roleplay the difficulty and struggle of bending their character's brains in a new direction.
Variations By Soul Spectrum Edit
Celesti have the fewest restrictions, being able to take any Path they like, being able to vary their Paths to any degree, and having relatively easy access to training and instruction.
Touched share most of the advantages that Celesti do, but their lower social standing in Celesti society makes access to magical education more difficult to obtain.
Light Children have a lot of freedom in their initial choice, but are constrained in their follow-on Paths - each Path must link, in some way, to a previous Path. Daisy, as a Light Child, might take a Path to create Portals, or to Alter the nature of a localized Space, as Paths related to Teleportation, which has a similar emphasis of reordering spacial reality. She might also take Telekinesis, appealing to the shared concept of motion. To make matters more difficult, Light Children have significantly fewer chances at a good magic education.
Vampires have similar restrictions on their Paths as Light Children, though older vampires obviously have had the time to make up for their limited educational opportunities through extensive self-experimentation and research. This self discovery often lends itself to a very nuanced approach, but also tends to make them specialists, doing magic that comes naturally to them, and spells that they would normally come up with themselves. "Mountains limit horizons" as the saying goes. Most Sires will give their Children some basic training, and magic styles and methods often flow through these lines. Younger vampires have begun to seek tuition from additional elders, or join collectives of fellow vampires of a similar experience level to train their skills and grow away from their Sire's domains, but the Sire/Childe relationship is still the most respected method of learning.
Djinn are more restricted in their choices - their initial and all subsequent Paths must in some way align with their Djinn nature. A Water Djinn has many spells and Paths relating to change, but it is a rare spell of theirs that promotes stability for any length of time, and never a whole Path. Most Djinn are taught in an apprenticeship to a Djinn of a similar type, due in equal parts to the general intolerance to Dead Inside, and the difficulty of a swiftly tilting world view - Efreets are even less likely to branch out, as their natures fully take over their lives. Getting a Water Efreet and an Earth Efreet to talk magic rarely works. At all. One comment on such an attempt was this: "It's like watching two people try and communicate by tapping out Morse code by slamming their heads into walls." In many ways, different Efreet, and to a lesser extent Djinn, do not share the same world as each other.
The most restricted magic users are the Reapers, because all of their Paths are limited to only one Soul Piece type, and all of their Spells must be, in some way, destructive. Complicating matters, most Reapers are made in return for service to another Shattered - an indenture that often leaves them with no magical education outside of what their masters provide, lest their secret be discovered; most masters leave that education to a strictly "need to know" level. A knowledgeable servant may be useful, but it can also be dangerous - especially given the destructive nature of most Reapers.