Costume Quest is an adventure role-playing video game developed by Double Fine and published by THQ. In the game, the player controls a child that is trick-or-treating with his or her younger sibling on Halloween night when they encounter a monster that kidnaps the sibling, thinking the candy-corn outfit is really candy. The player must travel around the local neighborhood collecting items for their costume, fellows children as companions and candy in order to face the monster and retrieve the sibling. The costume aspects are used in battle segments, where the player character and companions are transformed into the monsters and creatures they are dressed as to fight other monsters. The game is a downloadable title and will be released on October 20, 2010 on the Xbox Live Arcade and PlayStation Network services for $15 or 1200 Microsoft Points.
Source: Wikipedia, "Costume Quest," available under the CC-BY-SA License.