Cryptarithmetic: Rules, Strategy and Controls — a Player's Manual
Cryptarithmetic rules and controls: decode every letter to a unique digit, make the sum add up for real, and get mileage out of your three hints. Read more
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Hashiwokakero (Bridges): Rules, Strategy and Controls — a Player's Manual
Hashiwokakero rules and controls: give every island exactly as many bridges as its number, keep the whole network connected, and spend your five hints well. Read more
Hex: Rules, Strategy and Controls — a Player's Manual
Hex rules, controls and strategy in one page: how the connection game works, how the built-in AI scales with difficulty, and why a draw is impossible. Read more
Knight's Tour: Rules, Strategy and Controls — a Player's Manual
Knight's Tour rules and controls: visit every square exactly once with L-shaped jumps, survive with all 36 numbers placed, and learn Warnsdorff's classic trick. Read more
Masyu: Rules, Strategy and Controls — a Player's Manual
Masyu rules and controls: draw one closed loop through every pearl — black pearls force the turn, white pearls demand the straight — on grids up to 7×8. Read more
Peg Solitaire: Rules, Strategy and Controls — a Player's Manual
Peg Solitaire rules and controls for the 33-hole English board: how jumps work, why a win needs exactly 31 of them, and the strategies the cross rewards. Read more
Pipe Puzzle: Rules, Strategy and Controls — a Player's Manual
Pipe Puzzle rules and controls: rotate every tile back into one leak-free network, use your three hints well, and pick the board size from 5×5 to 11×11. Read more
Sudoku: Rules, Strategy and Controls — a Player's Manual
The rules of Sudoku step by step, the strategies that actually solve a board and every control — mouse, keyboard and gamepad. Deduction, not luck. Read more
Thermometers: Rules, Strategy and Controls — a Player's Manual
Thermometers: raise the mercury from each bulb, satisfy the row and column counts. Full rules, strategies and controls for this logic puzzle. Read more
The Spanish Deck: Six Centuries of Playing Cards in Four Suits
Coins, cups, swords and clubs: how the Spanish-suited deck kept its medieval pips for over six centuries, and why Klondike still works with it. Read more