I used a Space Eagle. Why didn’t it pop all the pigs?

The Space Eagle is there to help you with tricky levels, but it requires a little more skill to use than the Mighty Eagle. You have to pick a good spot to sling the can of sardines, then a Space Eagle will appear from a wormhole, popping the pigs around it. If you don't get all the pigs with your first try, you can use another Space Eagle to finish the job.