player already controls a stack of dolls, that stack can jump into a one-size-larger doll as well. The player can also unstack the dolls at any time in order to enter dolls smaller than his current stack. Certain unique dolls, outside of Charlie, have their own special abilities—such as the ability to unlock doors, float to higher locations, or lure other dolls around, which can be used by the outermost doll. Thus, the player must stack and unstack the set of dolls possessed by Charlie to solve puzzles throughout the game. Later puzzles may require the use of multiple dolls to combine their skills. The various challenges for each mission contain multiple solutions, with rewards offered for finding all of them. For example; in a challenge where the player must clear out a lounge of rich people, players can either sneak in a poorly dressed man into the party, or have another character flatulate into an air vent to clear everyone out. There are also rewards for completing side missions, discovering unique dolls, finding and stacking a matching set of dolls and performing "Hi-jinks" with certain dolls. Along with achievements and trophies, rewards can be viewed via dioramas constructed by Charlie's hobo friend, Levi. Development Stacking is the second game, following Costume Quest, to come from Double Fine that was initially created during an "Amnesia Fortnight" event during Brütal Legends development period. Tim Schafer had used the Fortnight during a time where the fate of Brütal Legends publication was unclear, dividing the company into four teams to prototype smaller games. The game's creator and project lead is Lee Petty, who had been the art director for Brütal Legend. Petty had wanted to create a contemporary adventure game, maintaining the characters and stories while reinventing the normal point-and-click interface used for such games. After observing his daughter playing with matryoshka dolls, he realized that the dolls themselves could be the characters, the inventory, and the action verbs at the same time. Petty and Schafer later reflected that the use of dolls, a common toy, would help to make the game appealing to the casual player, as they would quickly understand the mechanics of stacking and unstacking, while still having an allure for hardcore players with deeper gameplay mechanics. The idea of using these dolls would later be of benefit in production, as the basic structure of the doll model in the