The Cube 3x3 is a 3-D combination puzzle used as a critical-thinking and problem-solving tool. Do you want to sharpen your reasoning skill? Then grab your cube! Solving the Cube is a very good way of exercising the brain for both adults and children alike. It is a very good way of staying sharp and having a sound mind. This puzzle will challenge you mentally, it can also be used as a way of measuring someone intelligence quotient.