Launch the split bird pass the ice blocks. The purpose of this shot is to break the ice blocks holding up the metals in the back.
Power Activation Point
Activate the split up power shortly after you pass the first ice obstacle block.
First Shot Result
The metal blocks fall and kill the left two pigs.
Your second shot requires a bit of timing and accuracy. Aim for the base of the ice block that you intentionally missed for the first shot.
Second Power Activation Point
Right before you hit the ice blocks. Use your laser gun and aim for the bomb all the way to the right.
Second Shot Result
The bomb explodes and kill all the pigs. You will then earn your three star rating.