The key to passing this stage is to figure out the weak spots of the wooden blocks. All you have to do is to simply wear them down. Launch your first shot accordingly to the picture.
Power Activation Point
Activate the laser gun either down or to the left, your goal is to take out enough blocks.
First Shot Result
Below shows an example of when you take out the blocks.
Aim for the first platform.
Second Power Activation Point
Swing your sword to take out the pigs as well as some blocks.
Second Shot Result
Your result should be similar to the one in the picture.
Launch to finish off the rest of the pigs.
Third Power Activation Point
Your aim should take out the last blocks holding up the pig.
Third Shot Result
The lasers destroy the wooden block and kill the last of the pigs. You end up as a winner in the pursue for three star mastery.