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Forty Thieves: The Hardest Classic Solitaire?

Of the major solitaire variants, Forty Thieves consistently posts the lowest win rates among skilled players. Around 10% with strong play; 25% with theoretical optimal computer play. By comparison FreeCell wins 99% of hands, Klondike Turn 1 wins 33%, and Spider 4-Suit wins about 5%. Spider is technically lower, but Forty Thieves earns its reputation through a unique combination of brutal constraints. Here's why.

The Brutal Ruleset

Forty Thieves uses 104 cards (two standard decks). Ten tableau columns are dealt four cards each (40 face-up cards — the original "forty thieves"), with the remaining 64 cards in a stock pile.

The rules that combine to make the game punishing:

  1. Build down by suit only. A red 9 of hearts can land on a red 10 of hearts — never on a red 10 of diamonds. This restricts moves dramatically compared to Klondike's alternating-color rule.
  2. One card at a time. No group moves. Even a perfectly sorted sequence must be moved one card at a time, which is tedious and consumes valuable position turns.
  3. Empty columns only accept single cards. No Kings, no groups — and the single card is consumed immediately, not preserved as a workspace.
  4. Single pass through the stock. Once the stock runs out, no recycle. Cards in the waste are accessible only when they cycle to the top.
  5. No undo in classic play. Modern online versions allow undos, but classical Forty Thieves does not.

Each rule alone is fine. Stacked together, they create a game where a single misplaced card frequently doomed the hand.

The Math

With same-suit tableau builds, each card has only one legal landing spot per rank-and-suit combination. Compare Klondike (alternating colors): a red 7 can land on either of the two black 8s. In Forty Thieves, the red 7 of hearts can only land on the red 8 of hearts. Effective move options are cut by 50-75% per move.

Multiply this across 60+ moves per game and the total number of legal game paths shrinks from astronomical (Klondike) to small enough that many deals are simply unwinnable.

The Napoleon Connection

Forty Thieves is sometimes called "Napoleon at St. Helena," suggesting Napoleon played it during his 1815-1821 exile. The attribution is romantic but unverified — the game appears in published card-game books only in the 1880s, decades after Napoleon's death. But the name stuck.

The "Forty Thieves" name itself comes from the visual: 40 face-up cards at the start of the deal, like 40 thieves waiting to be captured. The captures (foundation moves) take all hand to accomplish.

Strategy for Survival

Strong Forty Thieves players use these tactics:

  1. Plan the foundation order. All 8 foundations must build A-to-K by suit. Plan which suit you'll prioritize based on what's exposed.
  2. Empty a column early. The single-card placement is a real handicap, but an empty column still lets you stage a problem card temporarily.
  3. Use the waste sparingly. Every stock flip exposes one card and consumes the waste position. Plan moves before flipping.
  4. Accept many losses. Skilled play wins 10% of hands. Don't mistake bad luck for bad play.

Easier Variants Exist

Several variants relax the rules:

Why People Play It

Despite the punishment, Forty Thieves has a dedicated following. Reasons:

Try It

Open Forty Thieves. Set aside 20 minutes. Expect to lose your first 5-10 hands while you learn the same-suit rhythm. After 30+ hands, your win rate should stabilize around 8-12%.