These are system design notes. This is not a finalized mechanic. Go ahead and play with it or try to find edge cases, but don't delete anything and don't expect it to work in-game. There are several variables visible to spell*casters*: Circle (Magery Pre-req), Spell Prereqs, unusual prereqs (see Keen Sense, Wish spells), cost, duration, casting time, spell type (Area, Knowledge, Normal, Blocking, Missile, Jet), resistance (HT, WL, IQ, active defense, none). Circle should set what is possible and what is not. Total possible power of a spell should be about C^2. Cost should scale linearly with effect — a damage-causing spell might be base cost 1 -1 (touch required) - 1 (HT resistance roll) +2 (two levels extra damage), for a circle of 2 (greatest single modifier, the +3 damage) and a cost of 1, and 3d damage. I think it's important to distinguish between: * Spells which directly affect a target. (e.g., Daze, Heal) * Spells which manifest an effect. (e.g., Mystic Mist) * Spells which create a medium. (e.g., Fireball) * Spells which incidentally affect a target. (e.g., holding up a symbol which has a Daze effect on everyone who looks at it) And to take into account spells which act through a layer of indirection (e.g. Invisibility) or have a metatarget (I cast a spell on you which turns any dogs near you blue). I refer to SpellParameters, which was something I wrote up a while ago thinking about spell effects (so it doesn't incude anything on prereqs). Use as you will. --zebediah