Temporarily increasing ability scores, and Spell Save DC

[Echoen]

Here is my understanding of how spells work:

Everything has to do with the time of casting. If your score is 16 at the time you cast your spell, the DC is based off that. If you later increase your score to 20, it does not retroactively increase your spell DC to spells you already cast.

However,

This interpretation seems to have caught my players by surprise - just as I'm surprised there was another interpretation. To their understanding, it is retroactive.

Any evidence to support one or the other?

[GreyWolfLord]

I'd go with it's DC is at the same level it was cast at. To attain a higher DC it would have to be recast at the higher level/DC in order to have that higher DC.

Unless there's something in the spell that specifically states it levels as you level...then the DC should be as it was when it was cast.

AT least that's how I would rule things like that...is there a specific instance you are referring to or a specific spell?

[DM_Blake]

I mostly agree with the OP.

While I can't find a single reference to support my opinion, I also cannot find a single reference to refute it.

For many effects, the caster starts the effect and then never thinks about it again. I would say that these effects cannot possibly be modified by changing the caster's stats - he's no longer controlling the spell or doing anything in any way with that spell.

For other effects, the effect is ongoing in such a way that it is apparent that the caster is influencing it. He might even be concentrating on maintaining it, or spending actions to directly influence the ongoing effect. In these cases, I can see both sides of the question - it seems that since the caster is still influencing the effect , he's still "part of it" or at least linked to it, then changing his stats might affect the effect. It also seems that the spell has been cast and the parameters set and it's possible that changing the caster's stats doesn't change the already-existing ongoing effect.

Since I can argue it both ways but only for some spells, while other spells the answer is very clear, I'm inclined to choose the ruling that makes all spells work the same way: No, changing a caster's stats after he creates an ongoing effect does not change that effect in any way, even if he's still mentally controlling the effect.

And since that is also the easiest solution (less math at the table), and the simplest solution (less to worry about), I think it's the best one.

[Joesi]

I've wondered about a somewhat similar issue involving casting Skinsend with temporary constitution.

Skinsend says one animates their skin as a creature which has half the hit points they had at casting. However if they had Bear's endurance on, that would increase its hit points even after it's worn off (especially since the skin has no Con score so there's no reasonable way that it could lose the health). I'd tend to think that temporary hit points would have the same effect as well, since temp HP is still HP.

[Lifat]

Yeah... I have to agree tbat there doesn't seem to be anything in the rules about either interpretation, but I'd also state that the GM has final say. The players should be the ones showing rules quotes, not you.

Personally speaking I'd rule that spells don't have retroactive higher DC's.

[James Risner]

There are no rules supporting either interpretation directly.

This is a great example of an "Ask your GM" question.

[David knott 242]

Do your players think that subsequent decreases to your intelligence reduce the save DC of spells already cast?

[James Risner]

David knott 242 wrote:

Do your players think that subsequent decreases to your intelligence reduce the save DC of spells already cast?

In the rules, decreases (damage/drain) are handled differently than increases.

[Create Mr. Pitt]

I am actually genuinely confused what this question is asking. While the buff is active the DCs going up. The DCs prior to activation wouldn't change retroactively; as in suddenly every spell you cast that day is of a higher DC. I am unclear how this can be controversial and feel like I must be missing something.

[Kaboogy]

The question is about spells with duration. Say my wizard casts flaming sphere. The spell includes a reflex save that depends on the wizard's int. What happens if I then buff the wizard's int by +2? Does the reflex DC go up by 1?

I'd say spells with concentration yes, spells without no.

[David knott 242]

James Risner wrote:

David knott 242 wrote:

Do your players think that subsequent decreases to your intelligence reduce the save DC of spells already cast?

In the rules, decreases (damage/drain) are handled differently than increases.

In what way do they differ that would be relevant to the topic of this thread?

The obvious case I can see this applying to would be a Hold Person spell. A wizard casts that spell, and one or more targets fail the initial save. I think most of us would assume that the subsequent saves would be made at the exact same save DC regardless of what happens to the caster afterwards, correct?

By the other interpretation -- Would the wizard casting Fox's Cunning on himself then increase the save DC by +2? Conversely, would a successful Feeblemind spell cast on the wizard reduce the save DC by an amount corresponding to the decrease in his intelligence modifier? Or, for the most extreme case -- what would the save DC be if the wizard has died? Since the spell does not require concentration, it could last past the wizard's death.

[Manwolf]

This is really up to the DM but I can't think of any situations that allow you to modify a spell after it has been cast, such as you can't use a metamagic feat after the fact, so why would a stat increase effect a spell that's already been cast? If you cast a flaming sphere a 2nd level spell, and then while your flaming sphere is still in effect, you took ability damage and were down to an 11 and you couldn't cast any more 2nd level spells, you wouldn't lose the current spell that is in effect, so why would it change the DC of the reflex save to avoid the current spell?

[Kaboogy]

Well, wouldn't you lose a spell that needs concentration?

[Create Mr. Pitt]

No, spells maintain of the DC they're cast at. Concentration is a really grey area, but that's quite a corner case; a caster would have to receive a buff while concentrating on the spell, I suspect that's rare.

[Manwolf]

I don't see anything about concentration or spell casting that says anything changes to an existing effect due to a change in your stat. Concentration spells either expire due to a maximum duration or you stop concentrating because you want to, someone breaks it, or you're unconscious.

All the rules are more about getting the spell cast in the first place. Odd situations like this subject to GM fiat.