Menger Sponge

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Teams receive a box that contains collection of 120 Magic Cards, grouped into 20 sets of 6 cards, each of which builds a cube. A group of six shares a number (1-20) and each card will be labelled with F (front), L (left), B (back), R (right), an up arrow (top), or a down arrow (bottom). For example, the first cube will be the cards labeled 1F, 1L, 1B, 1R, 1Up, and 1Down. These labels may be on the front or on the back of the card.

Along with the cards, teams also receive a sheet with building instructions that looks like this: