Pig Fortress

A Pig Fortress is what the Bad Piggies build to protect themselves against and slow down the Birds from retaking their eggs. The goal of the game is to kill all the pigs inside the fortresses and destroy the fortress. Pig Fortresses can be in any terrain: Mines, Campsites, Clouds, Normal Terrain, Construction sites, Desert, etc. Most of them are buildings, but some are seen to be methods of transport, for example, a tank-shaped structure in one level and wooden cars in a Golden Egg level. They mainly include materials such as ice, stone, and wood. They eventually get stronger in the later levels. In Angry Birds 2, it is set mainly in the air with plains in Cobalt Plateaus levels, Bamboo in Forest Levels and City in Pig City levels.

Terrains

 * 1) Plains (Worlds 1 and 4)1-1.png and Glass. This famous structure is also known as Poached Eggs 1-1. It is the very first level in the game.]]
 * 2) Deserts (World 3 and 5)
 * 3) Bamboo Gardens (World 2)
 * 4) Campsite (World 6)
 * 5) Skyline (Worlds 7 and 11)
 * 6) Clouds (World 8)
 * 7) Construction (Worlds 9-11 [based on themes from worlds 1-7])
 * 8) Wild West (Worlds 12–14)
 * 9) Mines (Worlds 15–17)
 * 10) Dessert Land (World 18–19)
 * 11) Bad Piggies Theme 1: Ground Hog Day (World 20)
 * 12) Bad Piggies Theme 3: When Pigs Fly (Worlds 21 and 22)
 * 13) Beach (Surf And Turf Levels 1 to 15)
 * 14) River (Surf and Turf Levels 16 to 30)
 * 15) Stormy Mountainside (Surf and Turf Levels 31 to 45)
 * 16) Bird Island (Bird Island 1 to 21)
 * 17) Farm Camp (Piggy Farm All levels)
 * 18) Prehistoric Jungle (Jurassic Pork first two worlds)
 * 19) Stormy Dead Mountains (Jurassic Pork last world 1–16)
 * 20) Dessert Land (All Birddays Worlds except 5)
 * 21) Blueprint (Birdday 5 All Worlds)