Fit all the 3D-puzzle pieces on the game board in such a way that it turns into a (flat) 2D-image.
One of the protruding sides of each puzzle piece has 1 ball, the other side has 2 balls. So depending on how you orientate a puzzle piece, you get more or less balls. When solved, all puzzle pieces will fit on the game board without any holes uncovered.
Playing this game stimulates the following cognitive skills: Concentration, Logic, Planning, Problem Solving, Spatial Insight