etrix-Ball twins - 2 colors - 16 magnetic pieces.
With plastic tiles: Skill Level.
How to play: remove the 16 pieces from the center core, and now try to put them all back on.
There are four different combinations to get all the pieces back on the ball,
Make a black and a white ball, half black half white
If you play with 2 Tetrix Balls, there are a total of 10 different combinations possible.
The 16 pieces can be placed inside the inner sphere, which can easily be opened for storage.