[Chaot]

Interesting. I'll take a look.

In the past, I've stolen/converted the AD&D spell system for BRP.

I've used Spell level equals MP expenditure plus a pyramid scheme. To know a second level spell you had to know two first level spells, etc. Make a Luck roll to get the spell off and include a MP:MP or POW:POW as needed for the spell.

I've also used spell skills, breaking it up into the various schools of magic: abjuration, conjuration, divination, enchantment, evocation, illusion, necromancy, and transmutation. MP= Spell Level. For spells that had more than one school there was only one skill role, but it had to equal a success for the given schools. Say someone was casting a spell from the evocation and illusion school. Say they had evocation at 60% and illusion at 40%. Say they roll a 10. Their evocation critical is at 12% and their illusion critical is at 8%. Use the lesser of the two to determine actually success rate. Said PC would have gotten a Success, not a Critical.

The other caveat in the skill system was that for every spell you learn, you had to have 20% per spell level of the spell you wanted to learn. So learning a 4th level spell would require the PC to have 80% in all the schools that the spell entailed. Learning a ninth level spell would require an 180% skill.

It worked really well.

EDIT: For the skill system:

Special: Spell goes off, no MP loss.
Critical: Spell goes off, 1 MP loss.
Success: Spell goes off, normal MP loss.
Failure: Spell doesn't go off, no MP loss.
Fumble: Spell doesn't go off, normal MP loss.