Aim your first shot at the top of the wooden block. This stage is pretty tricky that you have to get the exact timing correctly.
Power Activation Point
Activate the power well before you bump into the wooden block. You want the power coverage area to affect both the the metal pieces underneath. The goal is to use the metal pieces to break the two ice blocks underneath the pig all the way to the right.
First Shot Result
When done correctly, your first shot can kill all the pigs on screen. However, it may take several tries to pull it off.