Solitaire is played in two standard decks. Each of them contains 52 cards. After mixing 40 cards are dealt on the playing field in 10 columns of 4 cards each. They are face up, but only the cards of the lower row are recognized as playing cards. The rest of them will be played as they become available.
The rules are very simple. You are only allowed to move cards one by one. When you move a card it must be in placed in descending order and the same suit.
Empty columns allow you to restack more cards together, freeing up a card or a column in the process.
A card can only be added to a column if it is one rank lower and the same suit as the card that is being played on. You should start from Ace and gradually reach up to King
It is allowed to lay out any card which can be moved to the empty column.
There is a stock with the remaining cards set aside in a single face-down pile. But you can access it only if there are no possible moves, since you can turn over the reserve cards only once per game. The game is much more complicated than most solitaire games, you can’t alternate colors, move multiple cards at once or use the stack repeatedly.
A player wins Forty Thieves if all eight foundations are completely built from Ace to King.
As you can see, the Solitaire Forty Thieves is considered to be one of the most difficult solitaires what makes it an excellent logical game. You have to concentrate, plan your game and show patience, but the result is worth it. The solitaire perfectly trains concentration and analytical abilities.