Abstract: A puzzle which can be manufactured in several different versions, each version including a box that is open on top and containing nine blocks that must interfit a specific way so to fit into the box, and a separately purchasable expansion kit of four additional blocks for use in substitution of four blocks in the original puzzle so to vary the puzzle solution; the purchases kit being sold also with a drawer in which the unused four blocks and the puzzle box can be neatly stored together.