D&D General A puzzle about spell casting in D&D

[pemerton]

I've just been re-reading Gygax's description of spell-casting in his PHB and DMG. It talks about various components in spell casting, including the need for the somatic components to "be begun and completed without interruption in a clean, smooth motion" (DMG p 65) and the fact that "gestures must be exact and movements free and as prescribed" (PHB, p 100).

There are other class abilities in D&D that require exact hand motions to be completed cleanly - picking pockets, disarming traps, some weapon attacks - and since the earliest days these abilities have required a dice roll to determine whether or not the character successfully performs the motions in question. But generally it's never been required to make a roll to see if the somatic components can be properly performed. Why does spell-casting get this sort of benefit of the doubt?

 

[Krachek]

Simple.
You add a new rule. Casting cannot be done while grappling or restrained.
You playtest it.
And evaluate if it make the game more fun, strategic, dynamic. If so use it at your table.

 

[Don Durito]

Well if you got hit while casting a spell you automatically lost the spell. You didn't get a roll to see if you could keep concentrating on the spell.

It would seem that's where the description came from.

 

[Lanefan]

I've just been re-reading Gygax's description of spell-casting in his PHB and DMG. It talks about various components in spell casting, including the need for the somatic components to "be begun and completed without interruption in a clean, smooth motion" (DMG p 65) and the fact that "gestures must be exact and movements free and as prescribed" (PHB, p 100).

There are other class abilities in D&D that require exact hand motions to be completed cleanly - picking pockets, disarming traps, some weapon attacks - and since the earliest days these abilities have required a dice roll to determine whether or not the character successfully performs the motions in question.

One picky difference here: with a spell, in theory the required hand motions are exactly the same every time you cast that spell: "swish and flick"; and knowing the spell assumes you've also mastered those specific hand motions. With picking pockets etc. the required hand motions are unlikely to ever be exactly the same twice owing to different circumstances, different pocket location, different target item(s), different size/height/build of the target, etc.

And the target can potentially notice and interrupt you at any time.

But generally it's never been required to make a roll to see if the somatic components can be properly performed. Why does spell-casting get this sort of benefit of the doubt?

With casting in 1e, it's binary: you either get the spell away uninterrupted or you get interrupted and the spell auto-fails. Not until 3e does 'combat casting' arrive and muddy the waters.

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However, there is a tangential casting puzzle across all editions of D&D that has bothered me since day one: an archer has to roll to aim her shot; a person throwing a lit vial of oil has to roll to aim his throw, so why doesn't a caster have to roll to aim her ranged spell?

I've long since fixed this in my own game, but it still bugs me that the core game gives casters this huge (and IMO undeserved) advantage.

 

[ninjayeti]

'Cause that's what made sense to Gary Gygax on the day he wrote the rule. Having a single unifying concept or system wasn't really his thing. You might as well ask why do some of the Thief's abilities work a on a % chance, some x times out of 6, and the fighter's attacks off of a d20 roll.

 

[pemerton]

Simple.
You add a new rule. Casting cannot be done while grappling or restrained.
You playtest it.
And evaluate if it make the game more fun, strategic, dynamic. If so use it at your table.

Well if you got hit while casting a spell you automatically lost the spell. You didn't get a roll to see if you could keep concentrating on the spell.

It would seem that's where the description came from.

Yes, AD&D has a rule that you can't cast a spell while grappled etc. And you can't cast a spell with somatic components while prone or crouching.

But that doesn't answer the puzzle. You can't pick a pocket while restrained either, or while subject to a hold person spell. The question is why, when there is no restraint, can the player of the caster always, for free as it were, stipulate that his/her PC performs the hand motions correctly, but not in those other cases?

One picky difference here: with a spell, in theory the required hand motions are exactly the same every time you cast that spell: "swish and flick"; and knowing the spell assumes you've also mastered those specific hand motions. With picking pockets etc. the required hand motions are unlikely to ever be exactly the same twice owing to different circumstances, different pocket location, different target item(s), different size/height/build of the target, etc.

Gygax tells us that the hand motions for casting a spell "are usually required in order to control and specify the direction, target, area, etc., of the spell effects" (DMG p 40) so they won't be exactly the same every time.

And those versions of D&D that have rules for juggling or for sleight of hand like card tricks tend to require a check, even though those are non-magical feats of legerdemain in which the motions are the same every time the trick is performed.

 

[pemerton]

'Cause that's what made sense to Gary Gygax on the day he wrote the rule. Having a single unifying concept or system wasn't really his thing. You might as well ask why do some of the Thief's abilities work a on a % chance, some x times out of 6, and the fighter's attacks off of a d20 roll.

This feature of the system hasn't changed in the past 45 years, except for 4e D&D.

 

[billd91]

Gygax tells us that the hand motions for casting a spell "are usually required in order to control and specify the direction, target, area, etc., of the spell effects" (DMG p 40) so they won't be exactly the same every time.

And those versions of D&D that have rules for juggling or for sleight of hand like card tricks tend to require a check, even though those are non-magical feats of legerdemain in which the motions are the same every time the trick is performed.

Everything generally had some chance of failure. In the case of spells, there were saving throws and the occasional attack roll to govern much of that - as well as the interruptability. Thieving abilities, cobbled on a bit after the other mechanics, used a different method that probably seemed to work better for them at the time (probably because d100 offered more fine tuning for the abilities to get better per level, with racial bonuses, and stat bonuses, and (eventually) armor penalties).
Adding on some kind of system of spell success/failure based on a check the caster makes is just one more check to complicate the system - which would be excessively penalizing. It would be like making fumble checks for fighters or weapon/armor damage every time. And, for an adventuring RPG, that's getting more fussy than it's worth.

 

[Hriston]

I would say it’s for class balance. M-U’s have fewer hit points, no armor, and limited weapons. What they get is spells that work.

 

[Manbearcat]

I would say it’s for class balance. M-U’s have fewer hit points, no armor, and limited weapons. What they get is spells that work.

The problem here being it only does work until about level 6?

Level 7+ and M-Us start to accelerate. By level 9 they’ve reached Class Balance Escape Velocity. By 11 they’re on the moon. By 15, they’re a Type 2 Civilization!