Minus Cube Cube is 12 times more difficult to solve. However, if one does not confine oneself to these two types of the Minus Cube, there are 48 Minus Cube variants which can be solved. Minus Cube The Minus Cube () is a 3D mechanical variant of the n-puzzle which was manufactured in the Soviet Union. It consists of a bonded transparent plastic box containing seven small cubes, each glued together from two U-shape parts: one white and one coloured. The length of one side of the interior of the box is slightly more than twice the length of the side of
Void Cube retained by a trio of short circular flanges at the ends of the interior sliding pieces. When a face is rotated, those short flanges temporarily retain edge cubies, particularly when the face is rotated about 1/8 of a turn (roughly 45 degrees). As well, the corner cubies are temporarily retained by the curved flanges on the neighboring square pieces. During a rotation, flanges "change roles" as cubies travel along their circular paths. Void Cube The Void Cube is a 3-D mechanical puzzle similar to a Rubik's Cube, with the notable difference being that the center pieces are missing, which causes