One of the most versatile flies in the box the River Pig works well in a variety of situations. This variation is tied with a Marabou collar and XL Pseudo eyes allowing it get down quicker as well as cut through the water immediately and be fished as soon as landing.  With a floating line and Fluorocarbon leader it can fished quick with fast hard strips or you can lengthen out the leader to the depth of water and fish it slow bouncing bottom while still being able to manage your line. Best sets up for this fly I believe are with an intermediate line where it can be fish slow to fast with a variety of cadences allowing it dart and dive from the 60 degree bend hook as well with a full sink line where it can be fished very deep and cut through fast current to get below to soft water