Glibness

Glibness was a transmutation spell that altered the caster's speech, making his or her elocution much more convincing and believable.

Effects
The caster of this spell was blessed with an agility of speech that greatly increased the chance that a bluff would succeed. It even made magical means of detecting or preventing lies, such as discern lies, or a zone of truth, difficult and more likely to fail. The silver tongue ability lasted for 10 minutes per experience level of the caster.

Components
Only a somatic component was required to cast this spell, making it very subtle.