Forty Thieves Solitaire is a solitaire card game that also goes by the names Big Forty and Napoleon at St. Helena. It is a two deck solitaire game where the 10 tableau columns initially have 4 cards each that are face-up.
The goal of Forty Thieves Solitaire is to move all of the cards to the 8 foundation piles that are placed Ace through King. Once all of the cards are placed Ace through King, by suit, in the foundation you have won.
There are 4 main areas of the board in Forty Thieves: the 10 tableau columns, the 8 foundation piles, the deck, and the discard. As gameplay progresses cards are moved from the deck to the discard, discard to tableau or foundation, tableau to foundation or another column in the tableau.
To move a card onto a tableau column, from either another tableau column or the discard, the card must be one less and the same suit, or if the column is empty any card can be placed there. Cards can be placed on the foundation if they are one greater and the same suit.
In Forty Thieves Solitaire, the tableau is made up of 10 columns. Those columns initially have four face-up cards each.
The foundation has 8 piles, one for each suit of the two decks.
The deck contains initially all the cards that aren't in the tableau. The deck cards are face-down and are turned over to face-up when they are laid on the discard.
The discard is face-up and is initially empty. The cards are moved from the deck to the discard.
In Fun Solitaire's Forty Thieves Solitaire, the discard doesn't get recycled back into the deck. Also, cards in the foundation can't be brought back to the tableau.