In the interest of fairness, and sticking to a ball set with less than 100 balls, our Houdini game sheets are only available with 10 to 17 lines. In Houdini games, 2 numbers are often – but not always – called simultaneously. That is to say, that when a number is called, it’s reverse is also called at the exact same time. For example, if 14 is pulled, then both 14 and 41 are considered “called numbers” simultaneously – but not all of the numbers in the hopper can be reversed (ie: 11, 22, 33, 49, etc). In a 75-ball hopper, there are 21 numbers that are not reversible and 54 numbers that are. A Houdini game board is not considered to be “fair” for all players if some lines contain multiple non-reversible numbers OR if some lines contain 2 numbers that are reverses of each other (ie 24 and 42). Our Houdini boards solve this problem by randomly assigning a single unique (not reversible) number to each line – and then removing the remaining “unique” balls from play. The remaining 4 numbers for each line are randomly generated in such a way that makes it impossible for a line to have 2 numbers that reverse each other.

When you play your Houdini games within the Raffle Sheets app, only the numbers that are in play go into the hopper – and when a Houdini numbers is called – both balls (ie 14 and 42) are removed from the hopper. This makes for less boring games since there is never a number called which has already been dabbed or which doesn’t exist on any cards. Our animations also show both Houdini numbers being dabbed simultaneously. Try it!