How to play
Forty Thieves is the two-deck solitaire with a reputation for being tough. Everything is face up from the start, so there’s nothing hidden to blame; what makes it hard is that you can only ever move one card at a time, and the stock goes through just once.
The layout. Two full decks, 104 cards. Forty are dealt face up into ten columns of four, which is where the name comes from. The other 64 wait in the stock. Above the columns sit eight foundations, two for each suit, and a waste pile next to the stock.
The rules:
- Columns build down in suit. A 9 of spades can go on a 10 of spades, never on a 10 of clubs.
- Only single cards move. The top card of a column can go to another column or a foundation. A run of several cards can’t be lifted together.
- Any card fills an empty column. It doesn’t have to be a King.
- Foundations build up by suit, from Ace to King. With two decks, each suit gets two foundations.
- The stock is dealt one card at a time onto the waste, and the top waste card can be played to a column or foundation. There’s no redeal: once the stock is empty, it stays empty.
You win by getting all 104 cards to the foundations. When the remaining cards can all go up in order, a Finish button appears and plays them for you.
Tap a card to send it to its best spot or drag it where you want. Hint suggests a move, Undo reverses as many moves as you like, and your game is saved as you go.
Why single-card moves matter
In many solitaires, a neat run like 8-7-6-5 of hearts moves as a block. Here it has to be taken apart card by card, and every card needs somewhere to wait.
The only waiting room is an empty column. With one empty column, you can shift a two-card run: park the top card, move the second, bring the first back on top. With two empty columns, you can shift four cards in a careful sequence. Each extra empty column doubles how far you can rearrange things.
That’s why the whole game revolves around emptying columns, and why filling one carelessly is usually the biggest mistake.
Strategy
Empty a column early. Look at the ten starting columns for the one you can clear fastest, often a column with Aces and low cards that go straight to the foundations, or cards with clear destinations.
Get Aces and 2s up immediately. With two of each, there are eight Aces to free. Nothing can be built on an Ace in a column, so it’s dead weight anywhere but a foundation.
Guard empty columns. When a column clears, hold it open as working space. Put a card there only if it unblocks something important, and prefer a high card that can carry a long same-suit run down from it.
Build long runs carefully. Same-suit runs are hard to move later. A run of 6 cards sitting on a card you need may take three or more empty columns to relocate. Before stacking, ask whether you’ll need what’s underneath.
Play the waste before turning the stock. Cards on the waste are buried as new ones arrive, and with no redeal, a buried card is only recoverable by clearing everything on top of it. Move every waste card that has a home before you tap the stock.
Pick the right twin. With two copies of each card, you’ll often have two places to play one. Choose the move that helps the column that’s closer to emptying.
Accept the odds. Forty Thieves has a low win rate, even for strong players. A game that gets half the deck onto the foundations is a solid result.
For a one-deck game with more forgiving moves, try Klondike. Spider is the other classic two-deck challenge, with face-down cards instead of single-card moves.
If you enjoy Forty Thieves Solitaire, try FreeCell or Gin Rummy next.
