SRD:Elixir of Truth
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She is compelled to answer any questions put to her in that time, but with each question she is free to make a separate DC 13 Will save. If one of these secondary saves is successful, she doesn’t break free of the truth-compelling enchantment but also doesn’t have to answer that particular question. No more than one question can be asked each round. This is a mind-affecting compulsion enchantment.