Allowed moves
Match the cards that add up to 13. Matching is done by first clicking on the first card and then on the second. Only open cards can be matched. It doesn't matter where the cards are, you can match cards that are in the pyramid, in the waste, or in the temporary card pool.
Aces count 1, Jacks 11 and Queens 12. Important pairs are: Ace & Queen, Two & Jack, Three & Ten, Four & Nine, Five & Eight, Four and Nine.
There are 13 kings, and they can be removed by simply clicking on them.