Aim the R2-D2 at the base near the second tower. Your job for this shot is to kill all the pigs except for the two on the left.
Power Activation Point
Activate the power as you are about the hit the wall. This power should zap the piggy on the bottom right corner.
First Shot Result
The catapult launches and kill the pig inside the catapult. The only pigs left are the two on the left.
Aim for the middle of the first tower in between the two pigs. You will have to break the metal pillar to obtain a higher score.
Second Power Activation Point
Activate the R2-D2’s zapping power right before you hit the wall. It should kill both of the pigs.
Second Shot Result
Obtain the three star after zapping and breaking much of the house on the left side.