Games

Games and quizzes built to explore an idea, whether that's game-tree search on an ancient board game or a quick way to learn something by heart.

Terni Lapilli
Play a 2000-year-old tic-tac-toe variant against a minimax AI, with move evaluation and history shown live.
Cell Blocks
Shikaku and Fillomino, generated in the browser: each puzzle is verified to have exactly one solution and stamped with the deepest deduction it needs.
Nurikabe
Shade a sea around numbered islands. Boards are carved by repair, checked for a unique solution, and graded by the deepest rule they need.
Slitherlink
Draw one closed loop along the dots. Boards are generated by deleting clues while the solution stays unique, and graded by the deepest rule they need.
Kirchhoff
Draw arrows that conserve at every cell. Because feasibility is a max-flow computation rather than a search, this board can tell you whether your position is still winnable.
Guess the mark
A nautical chart, a highlighted buoy, and a multiple-choice question against the clock: learn the Solent racing marks.