I'm thinking about a couple of different ways to slice up spell access.Shared List, Explicit Access
(like D&D 3.x & 5e) - aka "Arbitrary Access" - Spells are on spell-lists, but there's no mechanical rhyme or reason to where or why. The class lists can't be simplified into a few rules -- the list itself is the rule by which you know if a character has access to a spell. New spells must explicitly know which lists they're on; new classes must either share a spell list with a pre-existing class, or define a new access list, which may or may not be supported by future supplements.
The problems with this access mechanism ought to be familiar to anyone who has been playing D&D for a while.Disjoint Access
- Each class has a distinct spell list. Some basic functionality may be duplicated, but overall a class has a distinct feel based on a totally exclusive spell list. Lists are never shared -- a new class must have its own list. This is how 4e did things, and it worked okay for 4e.
The problem of uneven supplement support persists, and there's a new problem: new classes (and homebrew classes) require a significant effort to create, since the author to draft new spell (or power) lists comparable to those of each base class. You can't easily bridge a concept like "swords + magic" by giving access to some pre-existing sword powers and some pre-written magic spells. You need to write a whole new set of balanced powers to represent that synergy. This can be difficult.Sublist Access
(like Tome of Battle) - Each "spell" list is distinct, with no overlap. Your class has access to one or more lists. Some lists are more common than others, and some lists have spells which are similar to spells on other lists, but the important thing is that each spell appears on exactly one list. Supplements are structured as new lists, and balance with old classes can be maintained by keeping rough parity in the number of lists to which each character has access -- in other words, you can write a new ToB discipline and allow characters to trade out one of their core disciplines for the new one, which creates novel play styles without guaranteed power creep. (Power creep can still happen, of course, if the new discipline is stronger than the discarded one...)
New classes are pretty easy: give some class features, and define a distinct sub-set of "spell" lists for your class. It's also much easier to introduce one new distinct, thematic list and augment that with a few pre-written, pre-balanced lists.
ToB mechanics make expansion & customization relatively easy.Tiered Access
(like Monte Cook's Arcana Evolved) - There are three types of spells:
- Simple (everyone has access to this small list)
- Complex (each class gets a subset of these, often based on descriptors)
- Exotic (nobody gets these by default; you have to expend character resources to pay for one)
One could look at 3.5e Psionics as this type of system, as well, at least from the Psion's perspective. There is a (large) group of basic Psion powers, then a sublist which each discipline gets, and then you can use a feat to buy an "off-list" power (from e.g. PsyWar or Ardent or Lurk), which you might not have been able to get any other way.
The neat thing about this is that supplements are much easier to balance. You can introduce new Exotic spells without much impact -- those are supposed to be rare, and must be paid for by each individual character. (In Arcana Evolved
, for example, each Exotic spell cost a feat, similar to the 3.5e XPH Expanded Knowledge [Psionic] feat.)
Complex spells can be added as long as you ensure that each package of new Complex spells is balanced across all descriptors. So, if you know the game has descriptors like Fire / Storm / Ice / Metal / Wood, then you can ensure each supplement introduces new content for each descriptor in roughly proportionate measure.
The most dangerous area for supplements is new Simple spells, because everyone automatically has access to those. This list should be augmented very carefully, and very seldom.
Finally, the issue of new classes, with access to a different set of descriptors -- these interact very well with new spells, if the supplements are always careful to balance new spells among all the various descriptors.
Adding a new descriptor is problematic, of course, so you should take care in covering as much conceptual space as the game is expected to support across its entire history.
You can also do the Descriptor / Keyword thing without any Tiers, too. I'll call this Descriptor Access
. Under that sort of system, you could have descriptors which are relatively abstract, and by using keywords to grant access, you can pretty easily create classes that are thematic, yet have very compact mechanics, and furthermore their mechanics will define access that includes new supplementary content automatically.
Here's an example of a few effects translated from a few 3.5e, level 2 spells:
- Glamour (illusions, enchantments, "fey stuff")
- Gnosis (self-imposition, willpower, "psi stuff")
- War (direct combat evocations & conjurations)
Each spell here has exactly one Tradition, and at least one Keyword.
Keywords: Hex, Illusion
Keywords: Light, Stasis
Gust of Wind
Keywords: Air, Storm
Keywords: Archon, Hex, Stasis
Keywords: Air, Illusion, Subtle
Keywords: Abjuration, Stasis
Keywords: Archon, Divination, Dragon
Keywords: Air, Hex, Subtle
Keywords: Air, Archon
So, what does this do for us? Well, you could make a "traditional" class, like a Warmage, and give them everything in the War tradition. That would work. (If you only had those 3 casting classes, you'd effectively create a Disjoint Access game using Descriptor Access rules.)
You could make classes that grant access across traditions, by keyword, like a Monk of the East Wind, who gets access to all Air spells.
You could make a Winter Witch, who gets all spells with at least one of: Divination, Hex, Illusion, Cold.
You could make a feat like Disciple of the Archons, which adds access to all Archon spells. ("Archon" is an abstract keyword that exists primarily to hang other effects on.)
You could also modify access by saying: "You follow a Chaos god. You are prohibited from casting any spell with the Archon or Stasis descriptor."
IMHO the two most interesting & viable mechanics are the Sublist Access
(like ToB), Tiered Access
(like Arcana Evolved), and Descriptor Access
So, which is better?
One distinction between the two is what happens when you try to augment a subset of effects with a customization option. For example, let's say you want to represent a character whose fire effects feel holy
, so you add a class feature / talent / feat like:
Generic Cleansing Sunfire
- Your fire effects are more damaging to undead & fiends, and when you use an effect that targets yourself, you can remove some detrimental conditions.
In the case of Sublist Access, you've generally got access to a sublist which favors that descriptor, or you don't. For example, in the ToB itself, there's exactly one discipline which features [Fire] effects, so you either have that discipline on your class list, or you don't.
Under Sublist Access, you'd probably write an option that targets a specific sublist:
Sublist Cleansing Sunfire
- When you damage a fiend or undead creature with a Desert Wind strike, you deal +X damage. When you use a Desert Wind boost, you may remove one of the following conditions from yourself: poisoned, shaken, hexed, ugly.
The upside of this sort of enhancement is that it's "self-contained", by being limited to one sublist, so you're unlikely to see unexpected interactions with a future supplement.
The downside is that the self-contained nature of the sublist means that you're unlikely to see any unexpected interactions in general.
Under Tiered Access or Descriptor Access, there are a lot of descriptors / keywords, so you can write a more general feature:
Descriptor Cleansing Sunfire
- When you damage an undead creature or a fiend with a [Light] or [Fire] effect, you deal +X damage. When you use a [Fire] or [Light] effect on yourself, you may dispel one detrimental condition with any of these descriptors: poison, fear, necromancy.
The immediate benefit is that your Desert Wind feat(ure) can improve your non-maneuver abilities, such as fire & light spells (for a Jade Phoenix Mage or a Ruby Knight Vindicator), or class features that are light effects (for a Shadow Sun Ninja).
Also, of course, a future discipline focused around Light or Fire would be able to benefit from the feat(ure) without modification.
So, which is better?
IMHO it's hands-down Descriptor Access
The flexibility of access, flexibility of augmentation, and flexibility of addition means that there's a huge design space available.
If there's interest in this sort of thing, I can show some of my ideas for what makes good descriptor design & helpful keyword choices.