Helicopter Cube a 6-member cycle, often referred to as its "orbit". Face center pieces in different orbits cannot be interchanged using only 180° twists. However, jumbling moves are able to permute face center pieces between different orbits, thus leaving the puzzle in a state that cannot be solved by 180° twists alone. Assume that Helicopter Cube is scrambled without jumbling moves (i.e. mixed with only 180 degree twists). Any permutation of the corners is possible, including odd permutations. Seven of the corners can be independently rotated, and the orientation of the eighth depends on the other seven, giving 8!×3 combinations. There are
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