This new puzzle challenges you to put six polycubes in a unit 3x3x3 box. So far, so good. But beware, this is a dynamic box packing problem where the enclosure has a rotating lid with a V-shaped void, so that you can insert pieces with specific sections and orientation only. This single solution problem makes completion a real struggle and is one of our hardest puzzles or so we believe.
 

• See at Puzzle Master