Mighty Hoax is the second episode of Angry Birds, which contains two themes with 21 levels each. Much like its preceding episode, it takes place once again in the vast plains. In the cutscenes, the pigs try again by stealing the bird's eggs, replacing them with cardboard cutouts, and using cardboard decoys to get away.
WHAT A DIRTY TRICK
When the birds awoke the next morning, the eggs looked safe and sound. Then Red looked more closely. Those sneaky pigs had returned to the Great Cliffs and replaced the real eggs with cardboard cut-outs! Spotting Smooth Cheeks grinning from a distance, Chuck threw himself at the King, knocking him flat. Too flat in fact. It was another cardboard decoy. Those swine are getting sneaky.
When the birds complete Theme 4-21, they discover the King they defeated was, in fact, a cardboard cutout, and that the real King is still out there. Later, the Birds finally succeed after destroying another cardboard cutout in Theme 5-21 and retrieve the eggs. The real King Pig retreats while the Birds celebrate their temporary victory.
King Pig sleeping behind a cartboard cutout of himself.
The original Mighty Hoax icon, showing the King Pig with eyes more tightly shut.
The original version of the Mighty Hoax intro cutscene
The current version of the Mighty Hoax intro cutscene