Everyone seems to have their own idea of how spells and spell casting should work. I’ve seen a great many spell systems and an enormous amount of diversity. Many DMs who play everything else strictly by the book still come up with their own unique spell casting system.

My system probably isn’t much different from others you have seen.

No Daily Memorization

First off, casters do not need to re-memorize spells every day. I always thought that concept was patently silly. Casters learn spells and know them from that point on. They can cast any spell they know but they can’t learn any spell beyond what their level allows. That’s a pretty standard basis for most spell systems.

Spell Energy

The limiting factor, that specifies how many spells a Wizard can cast in a day, is the character’s spell energy. A wizard’s total spell energy is equal to twice the character’s Intelligence times the character’s level. When a Wizard casts a spell, she rolls 1d12 and multiplies the result by the level of the spell. This is how much energy is required to cast the spell. If the caster does not have this much energy left, what energy the caster does have left is used up and the spell fizzles. She also takes damage equal to the difference between how much energy she had left and how much was needed to cast the spell. If that doesn’t kill her, there is still a chance that the caster will be dazed or knocked unconscious, or that the ability to cast that spell is ripped from her mind in the process. (I know I said earlier that casters don’t “forget” spells but this is different). If this happens, to regain the ability to cast that spell the Wizard must relearn it from her spell books.

Clerics

Clerics use spell levels instead of spell energy. The number of spell levels a Cleric has available each day is equal to twice the character’s Wisdom times the character’s level divided by five. It costs one spell level for each level of the spell being cast. So if a Cleric has five spell levels left, she can cast one fifth level spell or any combination of spells whose levels add up to five. There is no randomness and therefore no chance to attempt to use more spell levels than she has left. This is because she is using a spell casting ability bestowed upon her by her deity instead of attempting to access unpredictable magical energy as in the case of the Wizard.

Restoring Spell Energy & Spell Levels

Clerics regain spell levels, equal to their level plus their Wis bonus, after each hour of an extended rest.

Wizards regain spell energy, equal to 1d6 times the sum of their level plus their Int bonus, after each hour of an extended rest.

Just like natural healing, spell levels and spell energy may be regained at this rate even while on guard duty, so long as that consists of merely sitting and watching for intruders. Any interruption means that no gain takes place for the hour in which the interruption takes place. An extended rest may last up to ten hours and gains may only be received from one extended rest per day.

No Duplication

The published rulebooks have a lot of duplication of spells between Wizards and Clerics. I have gone through and assigned each spell to either the Wizard class or the Cleric class. There is no longer any duplication. This was partly done since characters may now easily train as both Wizards and Clerics and have access to both sets of spells in that way.

Spell Differences by Deity

Each deity grants different spells to their clerics. There is a great deal of crossover with many Clerics sharing a common spell base. But each deity also provides spells that are unique to clerics following that god.

Arcane Energy

Each deity has a specific alignment ranging from Law to Chaos and from Good to Evil. Clerics of deities of each alignment produce arcane energy that is unique to that alignment. This is readily apparent in the color of the energy produced. Regardless of alignment, all arcane energy produces the same effect and is essentially the opposite of necrotic energy.

Spell Level

What level do you have to be to cast a sixth level spell? That’s easy. You have to be sixth level. :)

I’ve gone through and reassigned the level of each spell so that spell level now corresponds to class level. A 12th level Cleric or Wizard can cast spells up to level 12. It just seems so much more sensible to me to match them up.

Learning Spells

Clerics don’t learn spells. Their deity gives them access to spells as the Cleric levels. The Cleric is immediately aware of these new spells.

Wizards learn two new spells automatically upon reaching each new level. This represents ongoing study and insight. Beyond that, any additional spells may only be learned from spell books or through research. Because of the enormous time requirements and resources needed to research a spell, this avenue is all but closed off for characters. Therefore characters must rely on finding spell books during their travels or convincing another Wizard to let them borrow their spell book to learn a spell.

Learning a spell from a spell book does not harm the book or erase the spell from the book. However, spells represent power and Wizards horde power. It is rare that a Wizard will allow anyone access to her spell books. On the occasions where this does happen, you can be sure that a great deal of money was paid for the privilege. Memorizing a new spell from a spell book takes one hour of uninterrupted study and reflection per level of the spell being learned. If this process is interrupted the Wizard must start over again from the beginning.

Spell Books

Spell books typically contain 50 pages and each spell written into a spell book requires one page per level of the spell. Because of their importance, spell books are always enchanted with protective magics to help keep them safe from harm. To add a spell to a spell book, the Wizard must first cast a ritual spell to prepare the book and then spend one hour, per level of the spell, writing the spell into the book. There is a cumulative 1% chance, per level of the spell, that the Wizard failed to scribe the spell correctly. In the case of failure or interruption, the full number of pages required to hold the spell are ruined. The preperatory ritual spell must be recast and the process started again.

Ritual Spells

Some spells require lengthy casting times (a few minutes to many hours) and expensive material components. These are referred to as Ritual Spells. In all other ways, they are identical to normal spells.