This game is written from the description of Pyramid by Hoyle.  The object is to remove all the cards in pairs.  Drag one EXPOSED card on to another AVAILABLE card when they add up to 13 to remove them.  A Jack counts as 11, Queen as 12, King as 13 (so you only need to double click on a single king to remove it).  A card is EXPOSED if it is on the Talon or if on the table there is no table card directly below it. A card is AVAILABLE if it is on the table and either is EXPOSED or it would be exposed if the card being moved was not present.