Smart Games IQ Plus Perplex Brain Teaser Puzzle 1-Player Ages 12+ (SMA524427)

There exist many packing problems with ball shaped puzzle pieces and probably even more based on cubes. IQ-Perplex is also based on cubes, but they are tilted on one of their corners. So although you would expect an orthogonal grid (as you normally would have with cubes), this results into an hexagonal grid. Theoretically you could also change the cubes to ball shapes. But if you did, you would loose the one thing that makes this puzzle game so perplexing: ball shapes are symmetrical in all directions, but cubes have specific orientations. When you place them like this on a grid, they overlap each other a little bit. And the combination of these properties gives this puzzle its surprising behavior.