Play your number cards carefully to keep the total between zero and 21. You have a hold slot and special cards to help you complete each level but you'll have to use those wisely.
Click on a card to add it to the main pile. When a card is added to the pile its number will either be added or subtracted from the total based on if a plus or minus sign precedes the number. Keep the total between 0 and 21 or you'll have to replay the level. To help you do this you can drag and drop a card on the "Hold" position. This allows you to keep from playing that card until it is needed.
The Min card sets the total to 1 when played while the Max card sets the total to 20. The Mid card (card with a dashed line through the middle) sets the total to 10. Earn enough diamond points and you will be able to delete a card by dropping it in the trash can.
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