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By early 2009, the links to the file went dead. Users who had hosted it on sites like Megaupload or MediaFire found their accounts deleted without explanation. The "Horsecore" thread on the old UnresolvedMysteries forums was scrubbed, leaving only a "404 Not Found" page. horsecore 2008 31 exclusive
If you can provide more context (where you saw it, what medium – audio/video/text, any other words or images), I can give a more precise identification. "horsecore 2008 31 exclusive