Mighty Hoax level 5-21 is a bit challenging. Our strategy is to fire the Black bird into the left side of the first tower, at least popping all pigs within. Use the two Yellow birds to pop any pigs that remain on the left side; otherwise, attack the base of the right tower. Use the first White bird to destroy the left half, then the second to destroy the right half of the last tower. The score in the video below is 183,920.