Joseph Manola has an article on “game-enhancing” and “game-ruining” powers. By “powers”, he largely means spells, but also magic item effects. He presents a list of some types of powers that game-enhancing — that “facilitate creative and intelligent play” — and some that are game-ruining — that have the potential to short-circuit many kinds of interesting play.

A “game-enhancing” example:

Levitation: Slow, vertical-only flight. Allows for all kinds of ingenious problem-solving but requires careful set-up, not particularly useful in combat, and generates hilarious mental images, especially if you allow levitating characters to be moved horizontally by party members pulling them along on ropes from below!

http://udan-adan.blogspot.com/2021/10/game-enhancing-powers-game-ruining.html

And a similar but “game-ruining” one:

Unlimited flight: Trivialises too many kinds of obstacles and opponents, especially if it comes with perfect manoeuvrability as well. If you want to give your PCs access to flight, try to build in some serious limitations.

http://udan-adan.blogspot.com/2021/10/game-enhancing-powers-game-ruining.html

I have taken Manola’s article, turned it into a checklist for filtering spell lists, and applied it to the Knave spell list. I’ve also made a few cuts and changes for idiosyncratic reasons that aren’t on the checklist. It’s my list, after all.

I’ve done this for my games, which are low-level, low-fantasy, and rules-light via Knave. The resulting list is going to be utilitarian, it’s going to lack much of the magic from fiction, and it’s not going to be perfectly compatible with published modules. But it’s likely to work for me with most of what I do. If you are not me, or you are doing something else, it might not work so well.

First, my checklist:

• Does it overlap with a key ability of another class? If so, cut.
  • (Knave is classless, so this doesn’t matter here, but in games with classes niche protection is important — otherwise, why have classes at all?)
• Is it a direct attack spell? If so, cut.
  • (They’re boring, overlap too much with combat skills and weapons, and well known for contributing to the “quadratic wizard” problem.)
• Is it something that can be duplicated by other reasonable, portable means, using the technology of the campaign setting. If so, cut.
  • (If magic replaces equipment planning, why bother with equipment?)
• Does it greatly weaken, or outright negate, the most powerful and meant-to-be-frightening threats in my games, in particular undead? If so, cut.
  • (I’m very, very into undead. But many D&D editions, in particular OSE RAW, give Clerics powers that wreck them easily.)
• Does it allow resurrection or straightforward access to the mind of a dead person? If so, cut.
  • (A key thematic element in the metaphysics of all my games is that death is the end — once you’re properly dead, you’re gone.)
• Does it allow mind control, mind reading or lie detection? If so, cut or at least severely constrain.
  • (Mind control can kill the social element of play, while mind-reading and lie-detection can slice through mysteries with little effort or interest)
• Is it otherwise Manola’s list of bad things (unlimited flight, unlimited intangiblity, mobility-while-still-attacking)? If so, cut or at least severely constrain.
  • (See Manola’s article for individual rationales)
• Is it simply too powerful for low-level Knaves to use safely, given the general feel of my worlds? If so, move to greater magic list (and give it a risk you run whenever you cast it).
• Does it provide a versatile building block for use in adventuring tactics, gambits, or plans? If so, try to keep. (narrow and restrict it if necessary to achieve that)

Second, the spell list, with commentary of what I’ve cut and why, is on its own page.

Finally, do you want a diegetic rationale for having such a limited spell list? For Knave, I say this:

In theory, magic can do an infinite variety of things, but in practice the vast majority of what you try achieves nothing at all. Scholars and seers and holders-forth-in-lecture-halls promote general theories of magic, not of which hold water beyond a very narrow scope. Most spells have been handed down from the distant past and at best been tweaked by modern practitioners. And you, as a Knave, are a pretty borderline practitioner.

So, anyone got thoughts?

(My main concern is that the resulting list is dry and utilitarian. But, then, the Knave list was dry to start with, partly because it’s so short. The best way to fix this is probably to add concrete detail of supernatural character — not just “An object of any size is pulled directly towards you” but “Four ghostly hands grip and object and pull…”, not just “L+1 objects are strongly magnetically repelled from each other” but “L+1 objects are possesed by animals spirits and write in disgust and pull away from another…”. That will take more space, but will make for better spells.)

Over on Monsters & Manuals, noisms dug some optional per-class xp rules out of the AD&D 2e DMG:

Fighters get XP for “defeating” enemies

Priests get XP for successfully using their powers, casting spells to further their ethos, and making stuff

Wizards get XP for casting spells to overcome “foes or problems”, researching things and making stuff

Rogues get XP for using their special abilities and, er, treasure

This sounds similar to (and was probably a direct ancestor of) “Keys” in the Shadow of Yesterday. There’s a pdf of that at http://downloads.darkon.info/pdf/tsoy.pdf — the list of standard Keys starts on p27.

I’ve had good times with Keys, but I’ve only used them in the kind of games (like tSoY) where we leap from scene to scene, resolving big conflicts in a single roll, and so forth. In a turns-and-rooms D&D game it would be harder to make them sing.