A (Reasonable?) Spellcasting Nerf

[Akennedy]

The concept behind this nerf is that magic is a hard art to learn to wield effectively. The spellcaster chooses schools of magic to "specialize" in, and the others have weaker then normal effects.
When a Character adopts a spellcasting class, she chooses 2 schools of magic to forgo. She chooses two schools of magic to have a caster level of 1/2 their spellcaster HD, two schools of magic to have a caster level of 3/4'ths their spellcaster HD, and finally, two schools of magic to receive the full caster level of their spellcasting HD.

In case that might be confusing, here's an example:
Hennet, the level 6 sorcerer, has chosen to have evocation and transmutation to be his two schools to magic to receive full caster level. Abjuration and divination, he's chosen, to receive 3/4th's his spell casting HD. Enchantment and Illusion have 1/2 his HD for a caster level. And he's decided to ignore to the necromancy and conjuration..
So, Hennet's caster level for Evoc. and Trans. is 6. For Abj. And Div. his caster level is 4. For Enchantment and Illusion his caster level is 3.

Is this an okay nerf?

[Drglenn]

How would Wizard's school specialisation work with this?
Would a specialised wizard have 3-4 barred schools?

[RTGoodman]

How would Wizard's school specialisation work with this?
Would a specialised wizard have 3-4 barred schools?

You could just assume that all wizards specialize (the ways Psions do), and therefore they all bar two schools.

[Spiryt]

Quite interesting I think. But firstly our experts should introduce our expertise about actual balance of it.

[Dryad]

Spellcasting as such is only over-powered on the short term. Instant kablooie wha hey. But any non-caster can swing a weapon all day long.
How about a sneak-attack nerf, then? Instant +10d6 dmg on... Well, if you're a tactical battlefield player, áll your attacks. Hmm.. Lessee.. Two weapon fighting, improved two weapon fighting, greater two-weapon fighting..
That's an additional 60d6 damage per round, on all hits. Why; it must be overpowered!

To kill spellcasting power, simply remove things like righteous might, and cut give a cleric Divine Spellfailure. Oh, and cut back their hit die to a d6. Suddenly, being support becomes a whole lot more interesting.

Wizards and sorcerors are powerful, yes. A wizard can cast most spells available, and a sorc can cast a lot of them, in comparison to a wizard, but...
Wizards can't just cast as they go along. They have to prepare spells, so for good offensive, you'll have to know what you're going up against.
Sorcerors are more limited, still. They simply don't have a choice; it's a small list, but you have to stick to it, no matter what.

Other classes can do their special abilities all day long, with exception to the bard, and druid. They can swing all day long, never run out of hits per day; that sort of thing. But a caster... After a long, tough battle, the casters are drained of their useful spells, and only have lower level spells at the ready, which might not do a lot of good, but also have a relatively low save dc.
And this is what causes the balance. Not the initial power, because casters are, indeed, very powerful, initially, but the limit to the uses of this power.

No, most other classes can't beat a full caster in a duel. But they will outlast most casters on the battlefield. Power and endurance, that's where the balance lies. And a caster lacks endurance.

[EvilElitest]

Spellcasting as such is only over-powered on the short term. Instant kablooie wha hey. But any non-caster can swing a weapon all day long.
How about a sneak-attack nerf, then? Instant +10d6 dmg on... Well, if you're a tactical battlefield player, áll your attacks. Hmm.. Lessee.. Two weapon fighting, improved two weapon fighting, greater two-weapon fighting..
That's an additional 60d6 damage per round, on all hits. Why; it must be overpowered!

To kill spellcasting power, simply remove things like righteous might, and cut give a cleric Divine Spellfailure. Oh, and cut back their hit die to a d6. Suddenly, being support becomes a whole lot more interesting.

Wizards and sorcerors are powerful, yes. A wizard can cast most spells available, and a sorc can cast a lot of them, in comparison to a wizard, but...
Wizards can't just cast as they go along. They have to prepare spells, so for good offensive, you'll have to know what you're going up against.
Sorcerors are more limited, still. They simply don't have a choice; it's a small list, but you have to stick to it, no matter what.

Other classes can do their special abilities all day long, with exception to the bard, and druid. They can swing all day long, never run out of hits per day; that sort of thing. But a caster... After a long, tough battle, the casters are drained of their useful spells, and only have lower level spells at the ready, which might not do a lot of good, but also have a relatively low save dc.
And this is what causes the balance. Not the initial power, because casters are, indeed, very powerful, initially, but the limit to the uses of this power.

No, most other classes can't beat a full caster in a duel. But they will outlast most casters on the battlefield. Power and endurance, that's where the balance lies. And a caster lacks endurance.

Be that as it may, i've always been under the impression that wizards and Clerics were some of the most overpowered classes in the game

Anyways, this new spellcasting system is a little confusing to me, could you plase explain it in more detail?
from,
EE

[Akennedy]

Well, EE, I'll explain whatever you would like me to!

All spellcasters would ban two schools from their list. They would then choose the other six schools to be divided into the following categories, two schools of magic per category.
Master - for these two schools of magic, they receive the full caster level for casting spells. Say, a level 7 sorcerer puts evocation under the master category and casts fireball, it will deal 7d6 damage.
Good - for the two schools of magic placed in this category, the caster level progresses as a medium base attack bonus would. So, if a level 7 sorcerer chose to put evocation in this category, it would deal 5d6 points of damage.
Poor - for the two schools of magic the caster decides to put in here, his caster level is progresses as a wizard's base attack bonus would. So, if a level 7 sorcerer chose evocation under the poor category, and is he casts fireball, it would deal 3d6 points of damage.

is that clear? :P

[Akennedy]

And Yes, as RTG said, wizards could NOT specialize. similar to psions, but not quite.

[Goober4473]

Dryad, a high level spellcaster will almost never run out of spells except in very rare circumstances, and even then, scrolls, wands, and staffs back them up. At low-mid level, they run out, and the fighter keeps swinging, but later is the problem, as I see it.

[Recursive]

I like the flavor, and the rough balance is good: a well-played full caster would be less dominant than she is now, but still a power to be contended with.

A couple of concerns:
- You might make this apply only to full casters. Partial casters (bards, rangers, paladins, etc) don't really need their magic nerfed.

- The "percentage of caster level" mechanic doesn't affect all schools equally. Evocation spells, for example, depend strongly on the caster level for their effectiveness, while enchantment and divination don't. (Reduced duration or range are a little inconvenient, but not nearly as crippling to the spell's effectiveness as reduced damage dice for a fireball.)

Instead of increased variety among spellcasters, you might find every wizard PC making the same "optimized" choices. ("Naw, you should never put divination above "Poor". Caster level doesn't matter there.")

So you might make the effects of mastery levels different for each school.
A few examples:

Evocation:
Master: full caster level
Good: 75% caster level
Poor: 50% caster level

Enchantment:
Master: full save DC
Good: -2 DC
Poor: -4 DC

Divination:
Master: functions normally
Good: 20% spell failure; 5% false results
Poor: 40% spell failure; 10% false results

...and so on, inventing meaningful penalties for each school.

As long as there's a good level of trust between the DM and the players, you could also tweak the system for individual spells: an enchantment spell which doesn't have a save DC could instead suffer level reduction or spell failure chance, for example. To keep this from becoming a micromanagement nightmare, just tell the players to expect any spell from a poor or good school to suffer some meaningful drawback, and let the DM make judgments on the fly about what that drawback is.