@Snarf Zagyg, I wonder if you're familiar with how
Beyond the Wall and its sister games (
Through Sunken Lands and
Grizzled Adventurers) handle magic.
There's only one caster class, the mage, and it has three types of magic: cantrips, spells, and rituals.
• Cantrips are weak effects that can be used repeatedly but have a chance of backfiring or reversing each time they're used.
• Spells are reliable but limited, with mages able to cast but one spell per level per day (with no Vancian memorization—if you know a spell, you can cast it). They take only a round to cast, and they're roughly on par with D&D 1st or 2nd level spells.
• And then there are rituals, which are divided into levels: 1st level mages can cast 1st level rituals, 2nd level mages can cast 2nd level rituals, etc. Each ritual takes one hour per level to cast, and as with cantrips, an Int or Wis check is rolled at the end of it, with failure indicating some kind of twist or unintended consequence accompanying the result of the ritual.
• A later addition to the game brought in a (dangerous and unreliable) way to bring the power of rituals to bear in combat. A 2nd level ritual called
The Patient Word can be performed in sequence with any other ritual in order to memorize it and have it stored in the caster's mind, volatile and ready to be triggered. The ritual can be cast at will; or, if you fail a cantrip or ritual roll while you have rituals memorized, you accidentally trigger
all of them. Even the wisest, smartest mages can only have at most three or four rituals memorized at a time, making this system feel even more properly Vancian than D&D. (Also, IIRC, each memorized ritual requires that the caster prepare a special wand or talisman which is then broken when the ritual effect is triggered; not necessarily expensive components, but they need to be magically significant and so may not always be as readily available as the caster might like.)
• A safer option is the 3rd level ritual Scribe Scroll, which works much like The Patient Word, but stores the magic in a scroll created via costly material components. A scroll isn't as volatile as a memorized spell, but it has two drawbacks. First, you have to make another casting roll to read the scroll, just as you did when first performing the stored ritual; failure on either check can result in a twisted, unpredictable effect. Second, it takes one round per ritual level to read a scroll—so you're trading speed for safety. For example,
Fireball in this system is a 6th level ritual, normally something that a mage would only cast from atop a tower at an oncoming army with six hours of ritual casting; if you memorize it with The Patient Word (which takes eight hours total), you can drop it in a round (but you can also very easily drop it on yourself by accident); while storing it in a Scribed Scroll (nine hours' total prep time) makes the
fireball castable in six rounds, tougher to pull off but much safer.
This is far and away my favorite magic system in any D&D-derived game. (In fact, I was on the verge of quitting D&D before I discovered
Beyond the Wall.) It's wonderfully written, the rituals are flavorful and interesting without being too edgy or convoluted (unlike some other OSR games I could mention), and it works really well in play.