At the beginning of the game, you draw five “lucky” cards that each features a 3x3 grid filled with numbers from 1 to 9, and with specific bonuses for each row and column. You pick three among these five and discard the other two. These lucky cards are to be written on during the game with dry erase markers that come with the game. Your goal is to achieve the highest possible score.
The game is played over four rounds. In each round, you will draw nine cards from the main deck. The deck is comprised of 18 cards numbered 1-9, with each card being featured twice. When you draw a card, you can cross one square (and no more) with a matching number on one of your lucky cards. If you want, you may spend Lightning tokens to modify the number shown on the card by as many tokens as you have spent (e.g. you can turn a 6 into an 8 by spending two tokens). If crossing a square makes you complete a row or a column, you win the corresponding bonus. It might allow you to cross another square, or you might earn a Lightning or a Moon token. Some bonuses are stars that give you bonus points at the end of the round.
At the end of the round, if you have completed a lucky card, you gain points depending on the round you are in (you gain more points in earlier rounds). Then, to prepare the next round, you draw three lucky cards and keep only one. At the end of the fourth round, you earn additional points for adjacent crossed squares, as well as for the number of Moon tokens you collected during the game. You can then tally up all your points to get your final score and see which tier you have achieved.