Pseudologia Fantastica (3.5e Flaw)
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You are a pathological liar.
Effect: Even if you don't mean to be a liar, you often cannot bring yourself to tell the truth, especially in pressure situations. If someone asks you a direct question (regardless of who they are), you must succeed at a Will save (DC 10 + Intimidate modifier of the questioner) or tell a lie. In addition, they gain a +4 bonus to saves made against a zone of truth spell. Depending on your Bluff skill, your interrogator might believe you, but just because you're a pathological liar doesn't necessarily make you a good liar.
Benefit: Bonus Feat.