Magic Mechanics

[chuckro]

So, I was musing on magic system mechanics for various roleplaying systems, and I figured I'd put this out there: Of the following, which do you prefer as a GM or as a player? Why?

1) Spells per day, typically that need to be memorized ahead and are expended when cast.

2) Spell-slot or spell-points systems, where each spell uses up a certain amount of MP or a slot that you regain when you rest. (A variation on this is spell-fatigue, where you don't get a MP limit, but casting tires your character and give you penalties to other rolls.)

3) Backlash systems (Paradox, primarily), where you have theoretically limitless magic, but risk backlash from using it/using it too much/using it in certain ways.

4) Percent-failure systems, where you again have theoretically limitless magic, but have to roll to succeed in using it and/or have a fixed percent-failure chance.

The follow-up/related question is whether you prefer free-form magic or a set spell list. And I'm not going to p[ost my opinions until I get a few responses, so as not to bias my sample.

Comments

[cubby-t-bear.livejournal.com]

Some hybrid mix of 2 and 3 (limited number of spell slots, flexibility in choosing which ones to cast at casting time, but possibility of backlash) fits best with my mental construct of fantasy magic, I suppose.

I've grown used to (1) after many many years of D&D. It dramatically weakens wizards at lower levels because of too few spell slots carrying situationally useful spells, but starting around 7th level or so, it gives immense flexibility and customizability. A massive variety of highly detailed, specific spell effects can be a pain to cope with, but it also allows you precise control over the type of effect you want to achieve.

In other words, I find (1) a lot like computer programming :) You have to pick which libraries to load, and you have to spend a lot of time with the references, but that gives you concrete, detailed, and extremely precise power to apply. Fantasy magic tends not to be like that in fiction, however :)

[chuckro.livejournal.com]

D&D magic, in practice, emulates fantasy fiction very poorly. If nothing else, there really isn't a system for "And then the spell went horribly wrong and turned us all into pigs." (Well, unless you're a wild mage, but even then, you need to deliberately invoke it.)

It's not surprising that I'm not the greatest at picking spells. I'm a crap programmer, too.

[cubby-t-bear.livejournal.com]

There is such a system, but only for idiots who try magic beyond their reach (see, e.g., scroll mishaps). So it's possible for the sorceror's apprentice, but not the sage sorceror who knows when he's playing with a spell above his level :)