full version offered for download from each platform's application store. The first update released on February 11, 2010 added a new episode called "Mighty Hoax", containing two new chapters with 21 levels each. Updates released on April 6, 2010 added the "Golden Eggs" feature, which placed hidden golden eggs throughout the game that would unlock bonus content when found, and a new episode called "Danger Above", which initially contained a single chapter of 15 levels. Two later updates added two more chapters to "Danger Above", each with 15 levels. "The Big Setup" episode, released on July 18, 2010, added a new chapter with 15 levels and additional Golden Egg levels. "The Big Setup" was later given two more chapters of 15 levels each. A fifth episode, called "Ham 'Em High", launched on December 23, 2010, in celebration of the game's first year in the iOS App Store. "Ham 'Em High" contained 15 American Old West-themed levels in a single chapter; updates on February 4, 2011 and March 18, 2011 each added one new 15-level chapter. "Ham 'Em High" also introduced the Mighty Eagle, a new bird that may be used once per hour to clear any uncompleted levels. The Mighty Eagle can also be used in previously completed levels, without the once-per-hour limit, to play a mini-game called "Total Destruction" in which the player attempts to destroy as much of the scenery as possible, both with the standard birds and the Mighty Eagle, achieving 100% destruction earns the player a Mighty Eagle feather for the level. The Mighty Eagle is offered as a one-time, in-game purchase, and was initially only available for iOS, as its App Store customers have iTunes accounts with pre-linked credit cards. In late 2011, Rovio also added the Mighty Eagle to the Chrome App version of the game. Rovio has begun testing an Android update called the "Bad Piggy Bank" with the Elisa wireless service in Finland and T-Mobile, which allows users to charge in-app purchases, such as the Mighty Eagle, to their mobile phone bills. The service went live on Android with the release of version 2.2.0 in August 2012, using Google Play's transaction system, which allows both mobile billing and credit cards, allowing both Android phones and WiFi-only tablets to unlock the features. This version also added the powerups from the Facebook version and added an option to pay to remove ads, allowing Android