Is there any way to know when a creature has succeeded a saving throw?

[Axoren]

Let's say that you cast an illusion spell and a creature interacts with it and succeeds their save. In this case, it's quite obvious if the creature succeeds their save because they'll walk through illusory walls, walk over not-actually-broken bridges, or ignore Optimus Prime's ranged attacks.

These cases I'm not concerned with. However, cases such as enchantment are less obvious. Let's say that you were to give someone a Suggestion. This lasts for a minimum of 3 hours (corruption subdomain). That's a fairly large amount of minimum time during which someone would be considering that Suggestion. They could do it immediately or they could take all 3 hours to do what you've "expertly recommended".

During those 3 hours, you're not necessarily aware if it worked. The target could have saved against the spell, been aware that you used the spell Suggestion, and been acting in a way that doesn't necessarily dismiss the possibility that they're suggested.

Are there any feats, spells, traits, class features, magic items, etc. that allow you to know with certainty when a creature fails a save?

[QuidEst]

It's built into spellcasting. There are ways around that, like specific magic items (e.g. Seducer's Bane), but generally you know if a target failed their save or not.

[Chemlak]

Only for targeted spells:

PRD, Magic wrote:

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.

[Axoren]

QuidEst wrote:

It's built into spellcasting. There are ways around that, like specific magic items (e.g. Seducer's Bane), but generally you know if a target failed their save or not.

Chemlak wrote:

Only for targeted spells

So, an area spell that affects up to X HD doesn't give that little ping?

But a one creature/level spell does, right?

[ShadowDax]

Axoren wrote:

QuidEst wrote:

It's built into spellcasting. There are ways around that, like specific magic items (e.g. Seducer's Bane), but generally you know if a target failed their save or not.

Chemlak wrote:

Only for targeted spells

So, an area spell that affects up to X HD doesn't give that little ping?

But a one creature/level spell does, right?

According to Chemlak, spells you cannot see you know their was an affect on you that failed to affect you, charm person, circle of death and the like. You don't know the name of the effect that was cast on you.

The castor knows the spells failed on a successfull saving throw with effects that cannot be seen. Spells with effects that you cannot see you know if they failed their saving throw. That is somewhere else though in the rules.

[Axoren]

ShadowDax wrote:

According to Chemlak, spells you cannot see you know their was an affect on you that failed to affect you, charm person, circle of death and the like. You don't know the name of the effect that was cast on you.

The castor knows the spells failed on a successfull saving throw with effects that cannot be seen. Spells with effects that you cannot see you know if they failed their saving throw. That is somewhere else though in the rules.

That didn't answer my questions, though.

I was asking for clarification on what counted as a "targeted spell".

[QuidEst]

Axoren wrote:

QuidEst wrote:

It's built into spellcasting. There are ways around that, like specific magic items (e.g. Seducer's Bane), but generally you know if a target failed their save or not.

Chemlak wrote:

Only for targeted spells

So, an area spell that affects up to X HD doesn't give that little ping?

But a one creature/level spell does, right?

Yep! You've got it.