Minesweeper: Murky Origins, One Famous Window
No known inventor; TechRadar, Eurogamer and the game's own author disagree. Then 1990, Windows, world records — and a genuine NP-complete theorem. Read more
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Nim: The Pile Game With a 1901 Theorem Inside
Nobody can date Nim's origin — but its winning strategy has a birthday: 1901, Charles Bouton, Harvard. Our computer opponent runs that theorem every turn. Read more
Kakuro: Rules, Strategy and Controls — a Player's Manual
Kakuro rules and controls: fill a digit crossword so every run adds to its clue with no repeats — arithmetic deduction, newspaper heritage. Read more
Nurikabe: Rules, Strategy and Controls — a Player's Manual
Nurikabe rules and controls: shade the sea, size every island to its number, keep the water in one piece and never let it pool in a 2×2 square. Read more
Slitherlink: Rules, Strategy and Controls — a Player's Manual
Slitherlink rules and controls: one closed loop along a dot grid, where every number 0-3 counts how many of its box's four edges the loop uses. Read more
The knight that crossed the whole board
A thousand years of the knight's tour: Sanskrit verse, Euler, the 1823 rule of Warnsdorff — and the tool that still uses it to photograph our own game. Read more
Why Our Puzzles Have a Single Solution
The WPC rulebook demands exactly one solution per puzzle. We opened our own generator code and asked every engine what it actually guarantees. Read more
299 ways to reason: a map of the World Puzzle Championship
The World Puzzle Championship is not one game but a bestiary of pencil-and-paper types. Here is the map by family — and where our 120-game catalog sits on it. Read more
Akari (Light Up): Rules, Strategy and Controls — a Player's Manual
Akari (Light Up) rules and controls: place bulbs so every free cell glows, no bulb shines on another, and each numbered wall gets exactly its count. Read more
Creek: Rules, Strategy and Controls — a Player's Manual
Creek is a shading puzzle where the numbers sit on the crossings, not in the cells — and every free cell must connect. Rules, strategies and controls. Read more