What is the eagle in Angry Birds?

In the video game franchise Angry Birds, developed by Rovio Entertainment, the "eagle" character is referred to as the Mighty Eagle. The Mighty Eagle is a special character that can be summoned by players to clear difficult levels. It behaves like a deus ex machina: when activated by using a can of sardines in-game, the Mighty Eagle flies across the screen with a mighty screech and plummets downward onto the level, causing massive destruction to the structures and pigs within. This character typically guarantees the player will pass the level, albeit without getting a star rating. Use of the Mighty Eagle is often limited to avoid undermining the challenge of the game, requiring either a one-time purchase or waiting a specific cool-down period before it can be used again.