Seventeen Puzzle - Hard Packing PuzzleChallenge even seasoned puzzlers with a 5x5x5 packing task. Fit seventeen wooden pieces into a compact cube. Pieces consist of blocks in differing sizes to increase difficulty. Trial and error alone will not suffice; planning and creativity are required. Invented by Cambridge mathematician John Conway. Ideal for stumping friends, family, or colleagues. Tests spatial reasoning and group problem solving skills.