How to play Forty Thieves

Forty Thieves is a classic two-deck patience, also known as Napoleon at St Helena. Forty cards are dealt face up into ten columns of four, the other sixty-four wait in the stock, and the aim is to build all eight foundations - two for each suit - up from Ace to King.

Every card on the table is visible from the start, but that is where the comfort ends. You may move only one card at a time, columns build down in the same suit, and the stock is turned one card at a time. Forty Thieves is famous for being hard: it rewards players who look several moves ahead, keep their empty columns for the right moment and resist the urge to play every card the stock offers.

How to play on skill.games

When you open the game, the settings popup appears. Choose a level - Easy, Normal or Hard (classic) - check your record at that level and press PLAY. The cards fly out onto the table and the game begins.

• Moving cards: tap a card and it goes to its best place: a foundation when that is safe, otherwise the card of its suit one rank higher, otherwise an empty column. Tap the top card of the waste the same way.
• Dragging: drag a card and drop it where you want it. A move that isn't allowed is refused: the card shakes and slides back.
• Double tap a card to send it straight to a foundation.
• The stock: tap it to turn its top card face up onto the waste. On Easy and Normal, an empty stock shows a circular arrow: tap it to turn the waste back over for your one redeal.
• Undo: the UNDO button at the top takes back your last move, as many times as you like, all the way back to the deal. On a computer, Ctrl+Z (or Cmd+Z) works too.
• The score line at the top shows your moves, the time and your score.

When every card that is left can go to the foundations, the game plays them up for you. Once all eight foundations reach their Kings, the cards cascade off the table and the results screen shows your moves, time and score, with your statistics for that level: wins, losses, win rate and streaks.

The menu button in the top-left corner pauses the game, starts a new deal or turns the sound off. The "?" button opens this guide. The deal is saved after every move, so you can close the page and press CONTINUE next time - even your undo history comes back. A deal you abandon by starting a new one counts as a loss at its level.

Rules

The cards. Two standard decks are shuffled together: 104 cards, two of every card.

The layout. Ten columns of four cards are dealt, all face up. The remaining 64 cards form the stock. Above the columns are eight foundations, two for each suit.

Foundations. Each foundation starts with an Ace and builds up in suit: Ace, 2, 3 and so on to the King. Either foundation of a suit can take the next card. Cards played to a foundation stay there.

Building in the columns. The top card of a column can be moved onto another column's top card when it is the same suit and one rank higher: the 6 of clubs on the 7 of clubs. Kings can only move to an empty column or a foundation.

One card at a time. The traditional rule is that only one card moves at a time. To save you tapping, the game will carry a run of the same suit in order as one move - but only when the empty columns would let you move those cards one by one anyway. With no empty column you can move one card, with one empty column two cards, with two empty columns four, and half that when the run itself is going into an empty column. If a run is too long, the game tells you how many cards can move.

Empty columns. Any card can be placed in an empty column.

The stock and the waste. Tapping the stock turns one card face up onto the waste. Only the top card of the waste can be played, onto a column or a foundation.

Redeals. On Hard you go through the stock once, as in the classic game: when it is empty, it is gone. On Easy and Normal you may turn the waste back over once, for a second pass through the cards.

Scoring. Every card played to a foundation scores 10 points. Every 30 seconds of play costs 30 points, although your score never drops below zero. When you win, a time bonus of 600,000 divided by the seconds you took is added. Undoing a move takes its points back, and an undo counts as a move.

Winning. You win when all 104 cards are on the eight foundations.

Strategy tips

• Free the Aces and 2s first. Low cards buried under four or five others hold everything up. Look for the moves that dig them out before you start turning the stock.
• Empty columns are gold. An empty column lets you shuffle cards around, park a key card or move longer runs. Empty one as early as you can and fill it only with a purpose - often with a card that unlocks another column.
• Don't play the stock too fast. A card turned onto the waste buries the one below it. Before you turn the next card, check whether the waste card could go somewhere first, and think about whether a move on the table should come before it.
• Build long same-suit runs carefully. A run in suit is easy to send to a foundation later, but it blocks the cards underneath it. Prefer runs that end on a card you will soon need anyway.
• Use both copies of each card. With two decks there are two 7s of hearts. If one is buried, the other may be the way to free a 6 of hearts - and the second foundation of a suit can catch the cards the first one can't take yet.
• Plan your redeal. On Easy and Normal, note which waste cards you could not use on the first pass; the second pass brings them back in the same order.

Difficulty levels

• Easy: one redeal, and every deal is one our computer player has already solved, so each Easy game can be won. If you get stuck, undo and look for the way out.
• Normal: a random deal with one redeal. The second pass through the stock makes most deals winnable with careful play.
• Hard (classic): the traditional game: a random deal and a single pass through the stock. Only a minority of deals can be won, and those that can demand precise play from the very first move.