standard tuning

that's the main riff played through the whole song

e|-----------0-----------------------0---------------|
B|-----------0-----------------------0---------------|
G|---------------------------------------------------|
D|-666\444-6--666\444-6-x--666\444-6---x-11-11-x-9-9-|
A|-666\444-6--666\444-6-x--666\444-6---x-11-11-x-9-9-|
E|-444\222-4--444\222-4-x--444\222-4---x-9--9--x-7-7-|

Sometimes after playing the main riff you hear this:

e|-------------------------------------------------|
B|-------------------------------------------------|
G|-------------------------------------------------|
D|-x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
A|-x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
E|-x-9--9--x-7-7-x-9--9--x-7-7-x-9--9--9--9--9--9--|

or this:

e|----------------------------------------------------------------------|
B|----------------------------------------------------------------------|
G|----------------------------------------------------------------------|
D|-4444444444444444444--x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
A|-4444444444444444444--x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
E|-2222222222222222222--x-9--9--x-7-7-x-9--9--x-7-7-x-9--9--9--9--9--9--|
   ...................

for the final part of the song, play the main riff like this:
e|---------------------------------------------------|
B|---------------------------------------------------|
G|---------------------------------------------------|
D|-666\444-6-x-666\444-6-x--666\444-6--x-11-11-x-9-9-|
A|-666\444-6-x-666\444-6-x--666\444-6--x-11-11-x-9-9-|
E|-444\222-4-x-444\222-4-x--444\222-4--x-9--9--x-7-7-|

at the end of the song play:

e|------------------------------------|
B|------------------------------------|
G|------------------------------------|
D|-4444444444444444444--x-11-11-x-9-9-|
A|-4444444444444444444--x-11-11-x-9-9-|
E|-2222222222222222222--x-9--9--x-7-7-|
   ...................

then

e|----------------------------------------------------------------------|
B|----------------------------------------------------------------------|
G|----------------------------------------------------------------------|
D|-4444444444444444444--x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
A|-4444444444444444444--x-11-11-x-9-9-x-11-11-x-9-9-x-11-11-11-11-11-11-|
E|-2222222222222222222--x-9--9--x-7-7-x-9--9--x-7-7-x-9--9--9--9--9--9--|
   ...................

. means palm muted on that chord

It's a simple song but it rocks!!
hope it's right, rate please!