Level 1-8
This difficult "Trick or Treat" level can be conquered with two birds if you are extremely careful. Aim the first bird at a high angle so that it hits the large stack of pumpkins just to the left of the center divide. If done correctly, this will explode the TNT and destroy most of the pumpkins to the right of the pile. Aim the second bird almost straight ahead so it takes out the remaining pumpkins and clears the level. You can earn three stars on this level, but only by finding just the right spot for the first bird.
Level 2-12
The first two birds are the large white ones. Launch them into the T-shaped section of concrete and drop the loads just before the bird hits the concrete. Launch the third bird into the exposed section of the tower. That should bring down the tower, the pig on the left as well as most of the pigs on the right. Use the final bird to finish off the remaining pigs.
Level 2-15
Aim the first red bird at the front of the building, just above the large pig at the bottom. That should collapse the wall and kill the front pumpkin. Aim the yellow bird at just about the same spot, which should collapse the rest of the left part of the building and kill the pumpkin located near the center. Aim the large bird so it hits the ground just before the large opening filled with pumpkins. If done correctly, the bird will roll enough to set off the TNT, destroying the pumpkins at the back and most of the pumpkins in the pit. Use the final bird to finish off the remaining pumpkins.
Level 3-10
Use the first two birds to aim at the base of the first tower. Those shots should cause the left tower to fall and take out the two pigs below. If you hit the tower just right, it will also take out the pig in the middle right section. Aim the third bird up in the sky and target the three pigs at the foot of the right tower. This should cause the right tower to fall on its left side, taking out the remainder of the pigs.
Level 3-11
The first bird is a small, red one. Aim it toward the ground just below the pumpkin pig. The red bird will bounce up and hit the diagonal plank next to the mustache pig and the chain reaction will take out both pigs. If done correctly, it will also set off the TNT, which will kill the helmeted pig. Aim the first yellow bird at the pig wearing the pumpkin hat. You are looking to also roll some of the planks and concrete to the right, taking out the pig below. Aim the three birds high in the sky to take out the big pumpkin head pig.