Now for a subject I’ve had trouble with since I started… but seem to have found a simple solution.
Not necessarily quick. There could be a lot of work in it, but I think I see ways to make it easier.
I’m going to leave out all the tedious thinking parts. They weren’t much fun to do, I don’t imagine they’d be much fun to read about.
Spell Casting
The good news is that I can probably use many existing spells almost as they are. I’ll have to adjust any modifiers they apply to checks (halve them so they work better on 3d6) and find alternate arrangements for things that modify or depend on ability scores (since I don’t have ability scores now). However, by and large I should be able to use existing spells as a framework.
It can be way easier to adjust something that exists than to create something new from whole cloth. This is one of those situations.
So, spells with levels from 0 through 9. I want abilities gained to be more or less appropriate for their level. This applies to path abilities, feat abilities, and in this case, spells.
If a character had a single class, or classes that all advance the same casting ability at each level, this is pretty straightforward. Just have a table of spell slots as is common, and advanced through it as class levels are gained.
I have a trickier situation. A character has four paths over their career, and it should be possible to have a mix of ‘caster’ and ‘not caster’ paths that still provide level-appropriate spells. The common mechanism would need to be bent out of recognition to make it work.
There’s another way.
Spell Level
Spell level is primarily to allow power to be gained at suitable levels. That is, a powerful and versatile spell is probably higher level than a spell that is as powerful but less versatile, or less powerful and as versatile.
In-game, it might be reasonable to say that casting more powerful spells requires more experience and training. Not necessarily because the spells are complex, but because they are powerful enough that errors could be disastrous.
Higher-level spells become available as a caster reaches higher character level. I will keep this.
Spell Complexity
Spell complexity, on the other hand, does not necessarily increase with spell level. Blasting away with bolts of lightning is powerful, but arguably not terribly complicated. At least, compared to other magic.
In-game, it could be reasonable to say that casting more complex spells requires more experience and training. Not necessarily because the spells are overly powerful, but because they are hard to do correctly.
I don’t know if I’ll keep this. I have an idea that could allow complex but lower-power spells to exist.
Spell Energy
Most D&D games have spells consume some kind of resource, to keep them from being overused and thus dominate the game. Usually this is spell slots that constrain how many spells of each spell level can be cast between recoveries. Sometimes this is spell points that are spent and recovered through various means. I have also seen games — not D&D games, mostly — that use fatigue to limit casting capacity.
I am not eager to use spell slots, because assigning and adjudicating them reasonably gets really complicated with the path system I’m using. However, I have already chosen a way to track effort investment.
Keith’s Choice
Overall, simpler than I expected.
- Maximum level of spell a character can cast is equal to one-half their level, rounded up. A character still needs to know a spell to cast it.
- Spell knowledge can be gained via path.
- Basic paths — if there is more than just ‘magician’ — give access to only the simplest spells. If I differentiate between types of magic (arcane, divine, etc.) that might show up here. Or it might not; basically everyone gets detect magic. Basic magic ranges from spell level 1 through spell level 6 (last basic path level is gained at character level 11).
- Expert paths get into more specific types of magic. Wizards and clerics are here, and their base spell selection comes from their magical tradition or their church. Expert paths range from character level 3 through character level 18; this naturally fits spell level 2 through spell level 9.
- Master paths get into specialized magic. Necromancers and other specialists are here, and deal with very obscure spells dedicated to their interests. Master paths range from character level 10 through character level 19; this naturally fits spell level 5 through spell level 10 (which doesn’t exist, but I’ll be back).
- Champion paths are going to use almost unique magic. I might go so far as to say champion casters might create traditions. Champion paths range from character level 14 through character level 20; this naturally fits spell level 7 through spell level 10.
- I have not yet decided if higher paths grant spell knowledge below the minimum level shown. I can imagine dedicated spell knowledge revealing obscure and complex spells that are not powerful enough to warrant higher-level casting. I can also imagine higher-path magic naturally falling into more powerful spells.
- A path (other than basic) likely grants knowledge of multiple sets of spells. The wizard path probably teaches ‘wizard spells’ (common to all wizards) and the wizard’s tradition teaches additional spells of two or three other types.
- Spell knowledge can be gained via feat. I don’t know exactly what this will look like, but I am considering a couple options.
- Feat lets the caster learn spells up to a level equal to the path number (i.e. master feat grant spell knowledge up to spell level 3). This seems awfully expensive for what is gained.
- Feat lets the caster learn spells up to the complexity of the path granting the feat, of a spell level up to the maximum the character can cast. That is, a master feat grants spell knowledge up to master complexity of a single type of magic. The feat would not give other benefits granted by a tradition (such as making traditional spells easier to cast), but the knowledge would be there.
- Casters might take these feats to learn spells outside their core training.
- Noncasters can take these feats so they know spells at all.
- Spells are cast using effort. The commitment needed will vary on spell level and training (path and association to the magic).
- A character casting one of their highest-level spells must commit effort for the day.
- A character casting one of their spells of the next two levels must commit effort for the scene.
- A character casting a lower-level spell must commit effort (i.e. not be exhausted, but recovers the effort when the spell ends).
- I expect these guidelines will be revised.
- Specific training might make certain spells easier or harder to cast (reduce or increase the degree of commitment required).
- Certain types of magic might be easier or harder to cast.
- Perhaps ‘expert spells’ require more effort, but an expert path reduces that again. ‘Noncasters’ without the path can still learn and cast the spells, but will find them more challenging than usual.
- There will probably be a casting check of some sort, and of course those who are formally trained (learn casting via a path) will be better at it.
I think that covers most of the basics of spell casting. The details are going to be tedious to fill in, but I think the rules themselves are fairly easy.