In This River Bass tab by Black Label Society

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In This River

G-----------------------------------------------------------------------------|
D-----10-------10--------10-----2-3-2-----------10--------10------10----------|
A-5--8-------8----------8--------3-------------5-8----------8-------8------\3-|
E----------6----------1--------------------------------------6-------1--------|

that's all there is to it really, this bassline goes along to the "in this river" 
version performed by BLS in the live youtube video, its easy to find and easy to play.