So this song is in the key of C. If its not exactly right then i think its very close, 
still kinda figuring it out as we speak but this should point you in the right direction.

--------------------|
--------------------|
------------------0-|
--5-3---5-3---5-3---|
6-----6-----3-------|
--------------------|


I think at some points the riff changes to this, maybe during all of the verses, but I'm 
100% sure about that.

------------------------|
------------------------|
------------------------|
--5-3---5-3---5-3---5-3-|
6-----6-----3-----3-----|
------------------------|

And these are the chords played during the chorus(it's not really a chorus but the part 
it gets intense)...

------------|
------------|
5----8------|
5----8----5-|
3----6----5-|
----------3-|

and this is played during this part also, I think it's just tremolo picked.
It's played throughout most of the song as well but it is much louder during the chorus.

--------|
--------|
--------|
---5----|
--------|
--------|

Well that's all I got...hope it's a decent tab!