Succeeding at a Saving Throw: A creature that successfully saves against a spell without obvious physical effects feels a hostile force or a tingle, but cannot deduce the exact nature of the attack. For example, if you secretly cast charm person on a character and his saving throw succeeds, he knows that someone used magic against him, but he can’t tell what you were trying to do. Likewise, if a creature’s saving throw succeeds against a targeted spell, such as charm person, you sense that the spell has failed. You do not sense when creatures succeed at saving throws against effect and area spells.
