If I case a spell on an invalid target, do I know why it failed?

[Michael Haneline]

If I cast a spell on an invalid target (for example, Charm Person on someone who looks human but is actually undead or an outsider) do I know that the spell failed to target them because they're an invalid target, or do I just know that it failed in the same way that I automatically know if they made their saving throw?

For example, I cast Charm Person twice: once on a vampire who has successfully disguised herself as a human, and once on her human lackey, who succeeds on his saving throw. Is the "failure feedback" different between the two?

[AwesomenessDog]

No, it just takes no effect as if your target passed a save. You don't normally know why a failed anyway, its just that via metagame, you can usually tell when a GM rolls a save vs when they don't.

[Michael Haneline]

AwesomenessDog wrote:

No, it just takes no effect as if your target passed a save. You don't normally know why a failed anyway, its just that via metagame, you can usually tell when a GM rolls a save vs when they don't.

Well specifically according to the PRD, the caster knows if a target makes a save against a spell unless it is an area spell.

[Michael Haneline]

https://www.d20pfsrd.com/magic/#TOC-Saving-Throw

"Succeeding on a Saving Throw

A creature that successfully saves against a spell that has no obvious physical effects feels a hostile force or a tingle, but cannot deduce the exact nature of the attack. Likewise, if a creature’s saving throw succeeds against a targeted spell, you sense that the spell has failed. You do not sense when creatures succeed on saves against effect and area spells."

[vhok]

does immunity just mean you automatically make your saving throw?

[Michael Haneline]

vhok wrote:

does immunity just mean you automatically make your saving throw?

No, immunity is treated as unbeatable spell resistance by the PRD.

So I guess that is a third facet to the conversation.

If I cast charm person 3 times: once on a vampire disguised as a human, once on their human lacky, and once on their drow lacky, and the spell fails all three times because of invalid target, successful save, and successful spell resistance, respectively, do I, as the caster, know that without metagaming?

[David knott 242]

Michael Haneline wrote:

vhok wrote:

does immunity just mean you automatically make your saving throw?

No, immunity is treated as unbeatable spell resistance by the PRD.

So I guess that is a third facet to the conversation.

If I cast charm person 3 times: once on a vampire disguised as a human, once on their human lacky, and once on their drow lacky, and the spell fails all three times because of invalid target, successful save, and successful spell resistance, respectively, do I, as the caster, know that without metagaming?

From the rule cited by Michael Haneline, yes you do.

For the human, we already have a rule citation that you know he made the saving throw.

For the vampire, the GM doesn't even make a saving throw. It would be misleading for the GM to say that the vampire succeeded or failed at the saving throw, as in fact he did neither.

For the drow, you had to make a roll to overcome his spell resistance. Since you failed at that roll, the saving throw becomes as irrelevant as it did in the case of the vampire.

In each case, the same magical sense that told you that the human made his save tells you that one of the other targets did not have to roll a saving throw and that the last target did not have to roll a saving throw after you attempted a roll to overcome his spell resistance. In all three cases, you can logically deduce that your spell failed, barring special abilities that permit one or more of your targets to conceal that fact.

[Claxon]

I don't think the rule cited here addresses what happens when a spell fails due to spell resistance or invalid target.

There's no elaboration on it. Only that you know when a target has succeeded on their save, for single target spells.

I think spell resistance should probably have some sort of visible manifestation.

Invalid target...I'm leaning towards you don't know but could deduce since you didn't get a notification of it failing, and you didn't see spell resistance.

Of course, certain targets might know to pretend like a charm person worked.

[Pizza Lord]

You only know that a ['spell that has no obvious physical effects'] failed if the target makes its saving throw. That is specifically spelled out and it is not implied anywhere that you otherwise know that a spelled failed for any other reason.

For instance, casting charm person:
• If it's an invalid target (a vampire or a dog that looks like a human), then you don't know whether it worked or failed.

• If its Spell Resistance isn't overcome, you don't know it failed (the target doesn't make a saving throw, and as such, you don't know the spelled failed, which is information that's only relayed when it succeeds on its saving throw). Even if in-character your GM wants to say that you know you are rolling an SR check, your character doesn't know what you rolled (unless you have a power that lets you know that) and even if you did know that you rolled it, you can only really know whether you rolled well, poorly, or in-between and that in no way indicates whether you passed or failed, just that a roll of a 2 is likely a failure while a roll of a 20 is a likely success... but that OOC knowledge might just make it more likely that you will be fooled if the creature is immune for another reason.

• If it's immune to charms, you don't know that it failed.

• If it's protected against the effects of charms (such as a spell that prevents control), then you don't know that the effect is suppressed. In this case specifically, the target would still make a save in case the protection spell wears off. So if it passed, you would know as normal, but if it failed you would get no indication of anything (though the implication would be that your spell succeeded). It just wouldn't do anything while they are protected.

In these cases, a knowledgeable target (Spellcraft) could know that you cast the spell and its intended effects and then pretend to be affected. For instance, a vampire could do what you ask to lull you into a false sense of security for a time (or to disguise that it isn't humanoid) and you would have no way of knowing that the spell is not working (unless you cast detect magic and realize there is no Charm magic aura active).

You also would have no way of knowing if the spell wore off early or was negated in some way. Of course, this is discussing charm person, there are obviously hundreds of spells and each one is specific and individual to itself, so there might be some that have effects that might be noticeable or detectable while still falling into the 'spell that has no obvious physical effects' category.

Obviously, as a player, if you see that your GM didn't roll a save, you could metagame and suddenly conclude that your spell failed, but that is obviously not appropriate. In character you would have to believably take an action to test it out; give a supposedly charmed target a command, cast detect magic and look for a suitable aura. etc. In any case, you get no indication of whether a spell with no obvious physical effects fails or succeeds except in the case of the target's successful saving throw and you certainly don't get to know why even if you figure out that it failed (whether it was an invalid target, whether you just happened to be in a dead magic zone or the target is in an antimagic field, or they're protected by a spell that makes them immune (or suppresses the effects of your spell, in which case they did make a save, but failed, which gives no indication to you, but it may take hold if their protection drops. Whether you know, notice, or can take advantage of it at that time is another story).

[Claxon]

In conclusion, there's a lot of reasons besides a successful save that could cause a spell to fail or be ineffective, and you have no direct notification to tell you that has happened.

[glass]

Michael Haneline wrote:

vhok wrote:

does immunity just mean you automatically make your saving throw?

No, immunity is treated as unbeatable spell resistance by the PRD.

Just to be clear, Magic Immunity (as is possesed by golems) is treated as infinite spell resistance. Immunity in general is just that; immunity.

The reason this matters is that fire immunity, for example, does not care about whether something has spell resistance (or even if something is a spell at all).

_
glass.

[David knott 242]

Normally, when a creature has spell resistance, the GM asks the player casting a spell for which it applies to roll a caster level check to overcome it. The request for a roll in and of itself gives the player a clue even if the GM does not reveal the result directly to the player.

Since a creature immune to magic effectively has infinite spell resistance, should the GM ask for a roll and then ignore the result (since it doesn't actually matter)? Or would it be more to the point to simply reveal that the creature is immune, since the alternative would be a pointless die roll?

[VoodistMonk]

I don't think there is any feedback to the caster outside of exactly what is written in the rules.

If you yell at a group of people, you don't know who heard you, who didn't hear you, who heard you but doesn't understand your language...

Don't give spellcasters any more than they already get. Period.

If the spell fails and there is no mechanism for you to know why, then you just wasted a spell for apparently no reason. It happens. And you may never learn what caused that spell to fail.

Every time a spellcaster casts a spell subject to Spell Resistance, they should roll their own CL check on the spot to determine what they get should the target have such Spell Resistance. The GM should not ask for these rolls only on enemies with SR... that is silly. Make the player roll their own CL check EVERY time they cast a spell subject to SR.

That way you, as the GM, knows the outcome... and the players do not.

[Ryze Kuja]

Your DM won't flat out tell you why it failed, but I'm sure you can guess why as a smart player, but as far as allowing your character to know what happened, you are allowed to ask your DM if you can use a combination of Knowledge Checks for Monster Lore and Recall Intrigue checks.

So use Arcana, Dungeoneering, Planes, Religion, Local, or Nature checks for Monster Lore to determine the vulnerabilities and special powers of any monster ranging from demons to fey to humans, and you can use a Knowledge check for Recall Intrigues to identify Class Features from classes that grant arcane or psychic (Arcana), druid/ranger (Nature), divine (Religion), or any other class (Local), as well as identify combat feats in use (Local), Metamagic Feats (Arcana), and Teamwork Feats in use (Nobility).

You can also make a General Knowledge check to Identify any Spells that are in effect (Knowledge Arcana 20+spell level DC).

^--- Using these knowledge checks, your character should be able to get you pretty close to gleaning "What" caused your spell to fail, if not outright figuring it out 100% as to what caused it to fail.

As to why a monster is unaffected by your spell, it's either because of a special power inherent to the monster (Monster Lore), a Feat or Class Feature that they're using (Recall Intrigues), or they have Spells (Identify) active. Or they simply made the Save <--- and there's no knowledge check that can tell you this part.

You can also use Spellcraft to identify Magical Equipment that might've caused it to fail, but you'd need approx 3 rounds of thorough examination to do so. <--- so this isn't very combat friendly

===============================

You can use these checks against every monster in the book, even humans. And the type of knowledge check you'll be rolling is dependent upon what it is you're attempting to identify, so this is something you need to be asking your DM in sesh before you make the check.

You: "I want to make a Recall Intrigues check vs. this demon that resisted my spell, and I want to know if he's using any class features, feats, teamwork feats that might've inhibited my spell"

DM: "Okay, make a Knowledge (Nobility) check." (Because this demon is using the Shake It Off teamwork feat)

You: "I would like to make a Monster Lore check to know if this particular demon has special powers w/ spell resistance"

DM: "Okay, make a Knowledge (Planes) check."

You: "I would like to make a General Knowledge check to Identify a spell that is in effect on this demon that would stop my spell from affecting him."

DM: "Okay, roll a Knowledge (Arcana) check."

Etc. Etc.

Side Note: Generally speaking, Knowledge checks do not take any actions at all. So you can make several checks, if you want to, but with Knowledge checks, there is No Retry. You either know it or you don't, and failing an Int check represents you were probably snoozing off in school when that fact was discussed.

[willuwontu]

RE: Immunity

A creature that's immune to a spell would actually roll its saving throw vs it, the spell would just have no effect even if it saved. E.G. You could cast fireball at a red dragon and it could just choose to let it wrap around it without singing a scale, or it could do a barrel roll to dodge and avoid the blast.

[Pizza Lord]

willuwontu wrote:

RE: Immunity

A creature that's immune to a spell would actually roll its saving throw vs it, the spell would just have no effect even if it saved. E.G. You could cast fireball at a red dragon and it could just choose to let it wrap around it without singing a scale, or it could do a barrel roll to dodge and avoid the blast.

Certainly, but in most cases they probably wouldn't. Once they roll for their save, they always risk rolling a Natural 1, in which case some of their gear might take damage. Just because the red dragon is immune to fire damage doesn't mean its magical [cloak/ring/bag of holding/whatever] is (it's not the same as a resist fire or protection from fire spell, which does specifically afford the same protection to the target's gear).

They might do it to trick their attackers into thinking they were afraid of that kind of attack, I suppose. To trick them into continuing to use fire. But in most cases, anyone with a reasonably good look can usually tell pretty easily that an attack is considered ineffective.

[VRMH]

A lot of good, sensible answers here, but I must ask: can you even cast a spell on an invalid target? Does the spell go off at all?

[Ryze Kuja]

VRMH wrote:

A lot of good, sensible answers here, but I must ask: can you even cast a spell on an invalid target? Does the spell go off at all?

Yes, and the spell fails and it is wasted.

Magic wrote:

Spell Failure

If you ever try to cast a spell in conditions where the characteristics of the spell cannot be made to conform, the casting fails and the spell is wasted.

Spells also fail if your concentration is broken and might fail if you’re wearing armor while casting a spell with somatic components.

So if you want to do your example in the first post, let's say a vampire or undead is using a mundane or a magical disguise and for w/e reason, you believe this vampire/undead to be a human. So you cast Charm Person on him. The spell immediately fails and is wasted, but you would not know that. The DM might even make a spellcraft roll for the Vampire to identify your spell as Charm Person, and try to trick you into believing the spell was successful, and you would never know.

[AwesomenessDog]

Pizza Lord wrote:

willuwontu wrote:

RE: Immunity

A creature that's immune to a spell would actually roll its saving throw vs it, the spell would just have no effect even if it saved. E.G. You could cast fireball at a red dragon and it could just choose to let it wrap around it without singing a scale, or it could do a barrel roll to dodge and avoid the blast.

Certainly, but in most cases they probably wouldn't. Once they roll for their save, they always risk rolling a Natural 1, in which case some of their gear might take damage. Just because the red dragon is immune to fire damage doesn't mean its magical [cloak/ring/bag of holding/whatever] is (it's not the same as a resist fire or protection from fire spell, which does specifically afford the same protection to the target's gear).

So if botching a saving throw causes your gear to melt, why doesn't simply not even attempting to save as if it were unattended?

Realistically, you still make the saving throw, because even if you don't give a damn, you still actually have to roll for your attended gear (and a dragon prob has a higher Ref save than any of his items).

[Pizza Lord]

That's correct, AwesomenessDog. That's certainly how I'd do it. I would roll a save and see if it came up as a natural 1 even if they were immune to see if an unprotected item might be damage. Similar to rolling to see if a burst weapon bursts on a critical threat even if you're hitting a creature immune to critical hits.

But there are likely some people that would say that if there's no roll then there's no Natural 1. Like, if you're unconscious or immobile you might not get a Reflex save (or automatically fail). That's not the same as rolling a Natural 1 though. I know how I'd do it as a GM, but I didn't want to bring up a whole different tangent to this conversation in the Rules Forum, since I am not 100% sure on the RAW of that.

[AwesomenessDog]

I mean more that even if you don't roll, the items would still have to, and since they use your bonus, you're rolling anyway...

That said, you still roll the reflex save while unconscious, but as you are helpless, your dex is treated as 0 for calculating your save. Basically a chance that the fires still singe you less, but you don't get your bonus to influence it.