You will most likely use two shots to get the three star for the stage, however you can potentially kill all the pigs with a single shot if you are lucky enough.
Aim straight towards the meteor rocks next to the bomb.
Power Activation Point
Swing your sword when you reach the rocks, your goal is to use the sword to set off the bomb.
First Shot Result
The TNT bomb explodes and push more rocks away, this chain reaction will be able to kill the majority of the pigs in this stage.
Use your second shot to pick up any loose ends. Swing your light saber wherever is applicable. You should be able to obtain the mastery of triple star once all the pigs are successfully destroyed.
Second Power Activation Point
Second Shot Result