Put another one on top! Small inventors find countless ways to stack up the colourful worry stones, which are flattened in different places. Stone is placed upon stone and there is plenty of fun as the stones wobble to find their balance. The game offers numerous possibilities for stacking the colourful wobbly rocks.. Playing with stability and balance trains the motor skills in particular. Inspired by one of the ancestral traditions of erecting stone mounds, with a colourful modern interpretation. Ideal for at home and on the move.