There is just one bass riff appearing in various places. It goes like that (for timing, 
to the song):

G:|-----------------|-----------------||
D:|-0-----2-3-------|-------0---------||
A:|-----------------|-3---------------||
E:|-----------------|-----------------||

G:|-----------------|-----------------||
D:|-0-----2-3-------|-------0---------||
A:|-----------------|-3---------------||
E:|-----------------|-----------------||

Thank you.