Two good things to do here...
One choice is a potentially very effective and powerful power shot, but there's a risk involved: Shoot the ball 4ball 2 rails into the 13 ball with speed, medium-hard, and draw-stiff the cueball sideways into the 12 balls thus sending a slew of balls towards your pocket - the downside gamble/risk to the shot is that you could catch a kiss from the 4 or 13 balls - probably worth the gamble though because you're going to get a lot of positive action from this shot...
The other, more conservative choice, is to shoot the 3ball...shooting to make the 3ball if that angle naturally sends the cueball behind the 4ball and down to the bottom rail and behind the 13ball...if you don't have that angle, then you play the cueball thinner off the 3ball, or fuller, shooting th 3ball into the 5-2 combination with a soft follow stroke - choosing whichever shot/angle will allow you to get the cueball between the 4 and the long rail, ending up down on the bottom rail and behind the 13ball.
- Ghost