This is a two-fold feat which can prove very helpful, or potentially harmful.
Firstly, you can now understand all spoken language, no matter the origin or age. This does not replace your character's known languages, in that you cannot read any language, you can only understand it if it is spoken. You retain the ability to only read those languages known to you. In addition, your Perception is increased by 2, giving you the ability to overhear conversations more clearly.
The secondary effect is that you must answer any question asked of you, personally, with the truth. You cannot not answer the question. The question must be posed directly to you. For example, the question "what brings you all here?" is not necessarily posed directly to you, so you may choose not to answer it. You must report the truth as you know it (if you were told something that turns out later to be a lie, at the time you answered you knew it to be the truth), and in as much detail as the questioner deems necessary. In other words, you can always answer a simple "yes" or "no" or "I don't know," any of which may be true, but if pressed for further details you must answer truthfully. If you attempt to lie, you will not be able to speak at all until the next full rest.
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