Why is Arcane Spell Failure a "Sacred Cow".

[The Sigil]

FWIW

There are a number of possible explanations, all of them somewhat plausible and all somewhat intertwined (is armor made to interfere with magic because of the nature of arcane magic or is the nature of magic made to be interfered with by armor because of the sacred cow?)

This gets into the nature of arcane vs. divine magic. I would suggest to you that there IS a difference... that they are not "different sides of the same coin" but that they are two fundamentally different animals.

The explanation that the PHB uses... that armor interferes with one's ability to cast arcane spells with somatic components... is okay with me. Why? Because arcane spellcasters rely on focusing and channelling ambient magical energy; part of the process by which it can be focused is gesture and positioning. The reason a spell cast with Still Spell takes up a higher spell slot is that it takes more effort to achieve the same effect without the positioning and gestures. IOW, the spell's efficacy comes from the character properly harnessing the ambient energy... and if done improperly, the spell doesn't work. Since part of the process of harnessing the energy may include somatic components, these are an important ingredient of arcane spells and doing them improperly results in improper focusing and therefore no effect.

OTOH, divine evergy does not rely on the character focusing ambient magical energy; rather, it is power granted to a character because of his faith. The somatic gestures in a divine spell are largely ceremonial - the power behind the spell is the character's deity rather than ambient magical energy. In other words, the spell's efficacy is derived from an investiture from deity rather than a channelling of outside energy. Since the process of spellcasting does not require harnessing some outside force but is rather motivated by a character's inner convictions, the somatic components are mostly for show.

When a mage casts a spell, he is channelling a neutral force of nature - ambient magical energy. When a divine caster casts a spell, he is calling upon the power of his god to be made manifest, rather than attempting to draw upon neutral ambient magical energy. That is the key difference... one reaches outward to the world around him (arcane) while the other reaches inward to his faith and convictions (divine).

That the effects are sometimes similar to arcane spells is coincidental; you can get roughly the same results using multiple methods - a blast of fire could come from arcane magic (fireball), divine magic (flame strike), alchemy (a really big batch of alchemist's fire) or "technology" (a flamethrower). While the results are nearly the same and have similar game effects, the motivating power is completely different.

Am I creating an explanation to help preserve a sacred cow? Maybe... but maybe not. Perhaps this explanation is what drives the arcane spell fail chance. Which came first, the chicken or the egg? Am I totally satisfied with the explanation? No... I think that if this is true there are further ramifications as far as spell effects go (notably as it relates to why do certain amounts of stone or lead block spells and shouldn't they be ineffective against divine spells). So I've included some bonus material below on how I *REALLY* feel about magic (as opposed to trying to explain the view I think went into the making of 3e).

Seriously, I'm sure I've rambled some, but there's my "take" on the matter. And, for good measure, here are some bonus thoughts...

ALTERNATE EXPLANATION DERIVED FROM PREVIOUS EDITIONS:

For a long time now, "magic" in D&D has followed a LOT of the same rules as mild radioactivity. Think about it for a moment... what can block a magical effect? A foot of stone... or an INCH (or less) of lead. This sounds VERY similar to radioactivity... lead blocks it much more efficiently than stone.

In fact, in the Mystara world, the source of magic was, as I recall, a radioactive hyperdrive from a starship which crashed into the planet millenia before the current campaign (changed into an artifact and amplified in intensity by the gods).

The following in fact contradicts the 3e rules as written, but I have always been of the opinion that the reason arcane magic is "interfered with" by armor is because of the "radioactivity" explanation. There is ambient magical energy ("radioactivity") everywhere; in order to cast spells, the mage reaches out with a heightened awareness to focus, channel, and shape the energy into the desired form (fireball, polymorph spell, etc.). Because metal does a good job "blocking" that energy, it does an equally good job of "blocking" the sensitivity of a mage... hence the spell fail chance... a mage simply has too much "stuff" in the way causing interference, keeping him from sensing and channelling the magic properly. In some of the campaigns I run, I play it this way... the Still Spell Feat does not affect spell fail chance.

Get a TV with an antenna (not a cable) and plug in your vacuum cleaner and run it near the TV... see the interference? The more armor you wear, the greater the interference... and the less chance you have of being able to properly interpret the images on the TV (aside from the vacuum cleaner noise). The same type of thing applies with arcane magic.

Divine magic, OTOH, is completely different. Here, the source of power is not ambient magical energy, but rather a direct investiture of power from the deity you worship. The source of power for a cleric is, literally, his deity. Hence, there is no chance of spell failure due to metal armor... unless you believe that metal blocks your faith and prayers or blocks the ability of a god to invest power within a follower.

This means that divine spells cannot be blocked by stone or lead... they are not radiation, they are due to power of a deity, which in theory should be omnipresent. IOW, divine magic is more powerful in its own way than arcane magic because it is harder to block. OTOH, because of the strict codes of conduct gods require in order to grant it in the first place - and the fact that a god can choose to deny the use of certain spells, it may be less powerful than arcane magic. With divine magic, you must have somebody else's agenda in mind (your deity's) while with arcane magic, you can have your own agenda. This makes arcane magic more flexible but also less powerful (in a way) because it is more easily blocked (since it operates according to "rules" while divine magic operates "because (a) god said so" - of course, this raises the "gods are just tough outsiders" argument... lol... we could go on forever).

--The Sigil

 

[JESawyer]

I was simply annoyed that there weren't canon feats for lowering ASF. I mean, COME ON, AC isn't even the issue. With a few spells and a decent Dex (and/or Cat's Grace to boot), a low level wizard can be more difficult to hit than most members of the party! A bard PC in one of my game routinely ran around with a 24 AC while wearing no physical armor.

 

[Henry]

What's so unplayable about casting your spells as if you were two levels lower?

That's the net effect of using still spell on your spells you wish to cast. All it requires, same as doing anything else fancy and out-of-type in D&D, is a feat.

We all know the history of this idea - but the fact that pure casters achieve some of a balance in this way cannot be underestimated. Sure, a caster's AC is plenty low as is, but imagine tacking another 4 to 8 points on to that already low AC?

 

[Uller]

Gron can't have everything Gron wants. If arcane casters could wear armor, that would increase their power quite a lot by removing one of their nastiest disadvantages.

Like I said...reducing ASF should be costly. Gron can't have everything he wants because everything he wants should be cost something, but shouldn't be impossible, IMO. I don't like to force characters that are something like ClassX/Wizard3 to have to rely on spells for defense or waste a feat and weaken their spell just to be able to cast in light armor. I don't like the Still Spell option. What if you only want to cast in Chain Shirt or Studded Leather? Should casting reliably have the same cost(Still Spell) as it does for casting in Full-plate and shield?


The house rule I've come up with will reduce ASF. It is easy to eleminate ASF altogether for the light armors(especially if they are Masterwork), but Heavy armors remain about the same and adding a shield makes things more difficult. For instance, a character with MW full-plate and a MW Lg Stl Shield and at least a 12 dex would suffer ASF 30% of the time. Make those mithral and give him a 16+ dex, it would still be 5%. With average dex and non MW stuff, it would be 45%.

And yes, I meant DC = 2(although, I'm leaning towards 3). Check is d20 + Dex + Armor Check...no skills allowed(or that would make it easier to reduce ASF to nothing with very little cost, IMO). So with the MW Full-plate, MW Lg Steel Shield and 12+ dex example the check would = d20 + 1(dex) - 5(MW Full-plate) - 1(MW Shield) = d20 + 5. You'd need to roll at least a 7 to pass so 30% failure(35%, 40% or 50% for DC = 3, 4, and 5 respectively...I'm actually leaning toward 3...).

 

[Uller]

What's so unplayable about casting your spells as if you were two levels lower?

If you are multiclassed, it becomes pretty unplayble, IMO. For instance a Fighter5/Sorcerer5. He's a tenth level character and he can only cast 1st level spells reliably AND it cost him a feat. Again, not saying he should be able to strap on some Full-Plate and a shield and have no chance of failure, but what about lighter armors? What about just reducing his failure rate 10% or 15% with a good dex and master work armor? Is that "unbalancing"? I have trouble looking at a 10th level character who can only cast Magic Missile and Shield reliably as being a worth while character...such a character would be better served just to be a pure fighter(or maybe a fighter9/sorcerer1). If I were to play such a character, I wouldn't feel like much of a sorcerer(considering my 10th level counterpart would be zapping foes with _Disintegrate_ and Enervation!).

 

[KnowTheToe]

Sigil,

long, but well articulated and thought out. Good Job!

 

[KnowTheToe]

That's almost exactly what happens if you take the Still Spell feat and apply it to all your spells which have somatic components.

I am smarted that I thought. I don't play magic users too often and don't know these little details.

 

[Uller]

Re: FWIW

There are a number of possible explanations...

--The Sigil

Great response, Sigil! Both explanations are somewhat plausible(perhaps a combination). Obviously, this is a game...so first and for most it seems to be a balance(or sacred cow) issue and any explanation is retrofit to the rule(it is magic, you can make it work anyway you want.

The "radioactive" thing works pretty well(even Leather armor could block the magic a bit). The precise movement thing doesn't, IMO.

Here's why: A character with 16+ dex can COMPLETELY negate the effects of Mithral Fullplate(+3 Max Dex, -3 Check penalty) when it comes to dex based skills like Move Silently, yet the same character cannot effect the ASF of even leather armor? I know...it's magic, but I can't reconcile that in my mind...

 

[Bastoche]

Why Clerics can cast in armor and not wizard ? Because they are wise enough to do so

 

[Ridley's Cohort]

The "radioactivity" thing is not an arbitrary idea.

There are a lot of references to magical or fey creatures being defeated by iron weapons. Remember your 1e MM? Presumably these stories started at the dawn of the iron age, when a rare smithy proved capable of making reliable iron/steel weapons and tools. One can speculate such a weapon would have a "magical" ability to break his opponents bronze weapons, making an otherwise merely competent warrior an instant hero fit for song.

So the idea that the right kind of metal tool can interfere with magical, fey, or diabolic influences is very old. Iron, silver, gold. They show up conspicuously all over the mythological material.

In short, the idea that iron and steel are somewhat "anti-magical" is a legitimate mythological tradition that predates D&D by millenia.

Another non-merlin, non-gandalf source of this sacred cow is medieval Christianity. It is part of the dogma of Christianity that magic is tainted by diabolic influences. Faith, relics, holy auras, powerful blessing were considered proof against diabolic influences. Christian knights were often very religious, especially the crusaders, and therefore had their swords and armor blessed. That implicitly recreates the ideal that steel swords and steel armor is anti-magical in nature.