It's a software update that automatically downloads to your game console and usually deals with fixing known bugs, problems or exploits that a game has. You need to be connected to the internet in order to receive it.
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I'm kind of disappointed that I just read through 4 pages of PA glitch talk and didn't get any feedback about the patch. =(
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Does anyone know if the PA Glitch can be fixed with a slider set? Just throwing that out there.