Question about SR [3.5]

[Fiery Diamond]

So I have a relatively simple question about spell resistance. Actually, two questions.

1) When casting a spell that affects more than one target that has spell resistance, do you roll versus spell resistance separately against each target or one single time applied to all targets?

2) Can you voluntarily fail against your caster level check against spell resistance?

[graeylin]

in my game worlds, each things SR is rolled.. thus, a fireball could impact hero 1, not bother hero 2, and impact hero 3 and 4.

and if i understand your question, yes, you can fail your check voluntarily (ie, lower your SR to 0) in order to be affected or effected by a spell cast.

[BobVosh]

If you magic missile and shoot 2 missiles at someone with SR you roll for each missile.

I'm not sure, but I want to say no.

[tyckspoon]

You can voluntarily lower Spell Resistance if you have it- it takes a standard action and means your SR will not protect you until your next turn. If you have it up, you cannot pick and choose what gets by it. All applicable spells must test, even helpful ones. And if its up, a caster cannot voluntarily fail against it; he must roll normally against it, even if he's hoping it will preserve his ally while he nukes the opponents standing around his friend. The closest you can get is casting your spell at the lowest valid caster level, which may defeat the point of casting the spell in the first place (for example, if you were level 10 you could choose to cast a Fireball at CL5, and it would have a much lower chance of breaking any level or CR appropriate Spell Resistance. It would also only do 5d6 damage, which probably is not why you wanted to cast it in the first place.)

..well, ok, that's not the *only* thing. You can take the Arcane Mastery feat, which lets you Take 10 on caster level checks, and then carefully calibrate your caster level so you automatically fail against the Spell Resistance you don't want to beat.

[unre9istered]

1) Not sure this is ever stated. I use 1 roll vs. multiple resistances.

2) I can't think of a check you can't voluntarily fail.

[Fiery Diamond]

and if i understand your question, yes, you can fail your check voluntarily (ie, lower your SR to 0) in order to be affected or effected by a spell cast.

This is not what I was asking. What I was asking was this. Say I am going to cast fireball. I have Spell Resistance. Can I do the following: cast the fireball with myself in the area, but voluntarily fail the caster level check versus my own SR, effectively making myself immune to the fireball.

Tyckspoon is saying no (although he's offering a way around it with Arcane Mastery and careful planning). Unre9istered is saying, well, that he can't think of a check you can't voluntarily fail. So the question remains - is there a RAW answer to this?

I don't seem to have a clear consensus on the other question's answer, either, although the majority seem to be saying to roll separately for each target. Does anyone know if this has a RAW answer?

[Gan The Grey]

A separate roll for each target doesn't exactly make sense. The whole point of the caster level check is to determine the potency of that particular spell. A fireball doesn't change once it reaches its target depending on how many targets there are in the area. Once it leaves the caster's hand, the fireball is what it is.

Let's say, Joe Wizardington, level 10, decides to cast fireball.

First, he casts the spell, deciding all relevant decidables in the process, i.e. range, location, amount of damage, ect.
Second, the DM lets Joe know that there are monsters in the AoE that have spell resistance.
Third, Mr. Wizardington rolls his caster level check to see if he can put enough 'umpf' behind his fireball to overcome spell resistance. He rolls 1d20, adds his caster level, and comes out with a 17.
Fourth, the spell leaves his outstretched hand, strikes the area, and the DM checks to see whether a 17 is good enough to overcome his monsters. One has a 15, one has none, and one has a 20. Two monsters are hurt, and one shrugs off the attack, moving forward to snack on Mr. Wizardington.

That, to me, makes the most sense.

[Fiery Diamond]

A separate roll for each target doesn't exactly make sense. The whole point of the caster level check is to determine the potency of that particular spell. A fireball doesn't change once it reaches its target depending on how many targets there are in the area. Once it leaves the caster's hand, the fireball is what it is.

Let's say, Joe Wizardington, level 10, decides to cast fireball.

First, he casts the spell, deciding all relevant decidables in the process, i.e. range, location, amount of damage, ect.
Second, the DM lets Joe know that there are monsters in the AoE that have spell resistance.
Third, Mr. Wizardington rolls his caster level check to see if he can put enough 'umpf' behind his fireball to overcome spell resistance. He rolls 1d20, adds his caster level, and comes out with a 17.
Fourth, the spell leaves his outstretched hand, strikes the area, and the DM checks to see whether a 17 is good enough to overcome his monsters. One has a 15, one has none, and one has a 20. Two monsters are hurt, and one shrugs off the attack, moving forward to snack on Mr. Wizardington.

That, to me, makes the most sense.

I think I agree with you; that does make the most sense, even if there isn't a definitive RAW answer. What about the other question, though?

For example...
Joe Wizardington, level 10, decides to cast fireball. Joe has an item that grants him SR 15.

First, he casts the spell, deciding all relevant decidables in the process, i.e. range, location, amount of damage, etc. He decides to include himself in the radius, along with 4 other monsters.

Second, he needs to roll to see whether he puts enough umph behind his fireball to see whether he overcomes the spell resistance of any creatures with SR in the radius. The DM doesn't need to tell him whether the monsters have SR because Joe has SR and thus needs to roll anyway. The DM knows, however, that 1 monster has SR 20, 1 monster has SR 15, 1 monster has SR 10, and 1 monster has no SR.

Here comes the dilemma.
Which of the following scenarios can happen?

1) Joe says, "I'm going to auto-fail my roll." Joe and the three monsters with SR are unaffected, and only the monster with no SR is affected.

2) Joe says, "I'm going to auto-fail my roll." This treats the roll as a 1, so the total is 11. 2 Monsters are affected (no SR and SR 10) and 2 Monsters plus Joe are unaffected.

3) Joe says, "I'm going to auto-fail my roll." The DM says, "I can't let you do that, Star Fox Joe Wizardington." Joe rolls the die and comes what may.

[Dr Bwaa]

I believe you roll separately against each thing with SR, so that a spell that would affect a group of individuals with the same SR value might affect some, all, or none of them. I (like everyone else) have no evidence for this.

Given this interpretation, I feel safe saying that you can't auto-fail your caster-level check, since you could then give yourself SR 1 and proceed to Fireball yourself with impunity every round.

Corollary: auto-fail means auto-fail. Just like you automatically succeed at dispelling your own spells (regardless of your current caster level vs your caster level when you cast the spell), if you choose to fail a roll, you just fail it; you don't treat it as a roll of 1; you treat it as a roll of $-\infty$ and simply fail whatever roll it was that you were making.
Pretend that this is formatted with LaTeX.

[Runestar]

Sr never interferes with your own spells.

In other words, your own sr will not protect you from the blast radius of your own fireball. :smallamused:

[Volkov]

DMG II says that you cannot voluntarily fail a spell resistance penetration check.

[Fiery Diamond]

Ah. Thanks for clearing that up for me. Very good to know.

[Douglas]

SR also specifically never blocks your own spells, so it is utterly useless for the "cast Fireball centered on myself" tactic.

[Irreverent Fool]

A note about voluntarily lowering your spell resistance:

You must lower it with a standard action EACH ROUND. If you don't, it comes back.

obnoxious
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