There might be more to it but from what I can work out this
riff is simply repeated through the whole of the song:
[ Tab from: http://www.guitaretab.com/t/the-drums/214666.html ]
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-/-7-7-7-7-7-7-7-6-4-4-4-4-4-4-4-2-0-0-0-0-0-0-0-4-2-2-2-2-2-2-4-6-|
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