You need two shots to kill all the pigs for the stage. However, you do not have to destroy the green jedi armor.
Aim at the bottom of the blocks with your first shot. You want to avoid having too many pieces flying to the top of the ice as your next shot will have hard time breaking them.
Power Activation Point
Activate your jedi sword at the base of the blocks.
First Shot Result
The tower falls, paving the path for you to kill the rest of the pigs.
Aim high so that you can get a clear shot to cut the ropes.
Second Power Activation Point
Tap for your lasers whenever you have a clear shot.
Second Shot Result
After you cut the ropes holding the metal blocks, they will fall and kill the rest of the pigs. You will then earn the three star rating.