One of the unique aspects of the new Xbox 360 game, Fable 2 is choosing between good and evil, enabling the player to make choices that affect the outcome of the game. This process is known as character morphing.Wikipedia: Fable II

Good and Evil in Fable 2 are determined by the player's choices that directly affect other characters in the game. Hitting the extreme on either side will result in the player character receiving either a halo or devil's horns. Some ways to be good include giving money to beggars and completing slave rescue requests. Some ways to be evil include indiscriminately murdering people or committing vandalism or theft.GamesRadar: Faces of Good and Evil in Fable II

Purity and Corruption in Fable 2 are determined by the player's choices that only impact themselves. Avoiding all meat and alcohol and being sexually responsible are ways to remain pure. Cheating on your spouse or showing off your trophies are ways to become corrupt.GamesRadar: Faces of Good and Evil in Fable II