Pyramid

Goal

Dismantle the 28-card pyramid by removing pairs whose value totals 13. Kings are worth 13 on their own and leave without a partner.

Values

• Ace = 1, cards 2 to 10 at face value, Jack = 11, Queen = 12, King = 13.
• Possible pairs: Ace and Queen, 2 and Jack, 3 and 10, 4 and 9, 5 and 8, 6 and 7.

How it works

• Only fully uncovered cards (with no card on top of them) are available, along with the top card of the waste pile.
• Tap the stock to turn a card onto the waste pile. The last three cards of the waste pile stay visible: the one on the right is the only one you can play.
• When the stock is empty, you can rebuild it from the waste pile depending on the level: unlimited passes (Easy), three passes (Medium), two passes (Hard and Expert), a single pass (Devilish).
• The game is won as soon as the pyramid is completely dismantled; the stock does not need to be emptied.

Controls

• Tap a card: if only one partner is available, the pair leaves by itself; otherwise the card is selected and its possible partners light up.
• Drag and drop a card onto its partner, or a King onto the pile of removed cards.
• Keyboard: Space to draw, I for a hint, Ctrl+Z to undo, Esc to deselect.

Scoring

• Pyramid card: 10; waste pile card: 5; fully cleared row: 25.
• Win: 250, together with 1 for each second under the 10-minute mark and 100 for each unused pass (levels with limited passes).

About the solver

Each deal is chosen by an exact solver that plays the game with the cards face up, in a separate thread: depth-first search with a transposition table (the 1,430 possible shapes of the pyramid are indexed) and pruning of dead positions (a card deprived of any partner, balance of complementary ranks, blocked waste pile in single-pass mode). Difficulty is measured by the number of dead ends explored before the solution. The hint queries the same solver on the current position, so it knows the order of the stock. The deal number lets you replay a game identically.