From the box:
'Ten different digits make up the world of numbers that define how we live: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. What if there weren't ten anymore? What if the number '9' suddenly disappeared forever? Everything would change - the way we count, our age, the way we tell the time, possibly even our shoe size!'
Players race to reach the target number (from the roll of an 8-sided die), using the numbers on 8 randomly chosen, double-sided tiles, using base 9 arithmetic.