Hmmm, 79 or 80 with defect. There is section in BESM which details a guideline how determine defects for your spells and how they work. There is ritual, shamanism and wizardry styles listed there. Ritual asks several participants, shamanism asks lots of time prepare/mediate while wizardry is more immediate but it drains energy points.
Overall though spellcraft (offensive anyways) comes in with weapon attribute. You can have forcefields, conjured armor rating or elemental related telekinesis for other spells. Or summoning spells even.