http://angrybirds.wikia.com/wiki/Mechanic_Pig

The Mechanic Pig is a side character and the primary deuratagonist in Bad Piggies, that can be hired to automatically construct vehicles that can pass the level in case the player is stuck. He is the Bad Piggies equivalent of the Mighty Eagle. He also appears in the Angry Birds episode Bad Piggies, where he helps the pigs steal the eggs and defend themselves from the birds by using his mechanic skills.