This pig wears an army helmet that protects him from direct damage and falling from a certain height.
Golden Pig
Can appear anywhere, but only rarely.
When popped, this pig will instantly fill the Destruct-O-Bar, immediately giving you an extra bird if applicable. Does not have to be popped to complete the stage.
Umbrella Pig
Can appear anywhere, though is much more common in rainy levels
When caught in the air, this pig will float down very slowly. His umbrella also shields projectiles.
Balloon Pig
Can appear anywhere
This pig can randomly inflate a balloon and fly into a high area.
Rocket Pig
Can appear anywhere
When a bird comes near him, this pig flies out of danger then slowly descends with a parachute.
Snow Pig
Uncommon in most levels, common in boss levels, and very common in snowy themed levels
This pig shoots snowballs every so often. If a bird gets hit by one, it loses all of its momentum and will just fall. Somewhat ironically, his snowballs can damage bosses severely.
Construction Pig
Commonly in intermediate levels
This pig throws screwdrivers at your birds, which will knock them away if hit by one.
Crystal Pig
Commonly in intermediate levels
This pig uses his crystal wand to fire magic bolts at your birds, turning them into a random object if hit by one. The bolts can also travel through portals, vents, and walls.
Fire Pig
Rarely in intermediate and hard levels
This pig shoots fire at your birds, which will make them instantly disappear if hit.
Magic Pig
Level 241 and beyond
When this pig is in danger, he teleports (2 times maximum) to a random location, away from the destruction.
Chemist Pig
Levels 321 and beyond
When popped, this pig turns all blocks into the same element (Glass, wood, or stone).
Angry Pig
Level 401 and beyond
When popped, this pig explodes, damaging structures around it, just like a TNT Box.
Swimmer Pig
Common enemy, appears in water levels
Floats on water.
Scuba Pig
Rare enemy, appears in water levels
Immune to drowning.
Astro Pig
Level 581 and beyond
When popped, nearby pigs and blocks will be temporarily levitated into the air, and then dropped.
Beamer Pig
Level 861 and beyond
When a bird gets close enough, this pig will pull your bird towards him with a tractor beam.
Trivia
There's a rare chance (Of 1/5) of a special pig lose it's speciality after hit but not defeated by a bird.