Games
Puzzle and chess games built around the same things as the books: logic, patterns, and a little mathematics.
Puzzle game · web, iOS, Android
Hexakai
Hexakai is a Sudoku-inspired game of hexagons, played on a hexagonal diamond-shaped grid of cells with boards ranging in a wide variety of sizes and difficulties. There is a new daily puzzle, plus strategy lessons and a blog.
Play free in your browser or in the apps. Hexakai Plus is an optional subscription with extra features; see hexakai.com/plus (opens in a new tab).
Prefer paper? Hexakai: the puzzle book has 150 puzzles, strategies and the mathematics behind the game.
Puzzle game · web
Hyperkai Beta
Hyperkai is a hyperbolic puzzle game from the maker of Hexakai: a Sudoku-inspired puzzle on a board of tiles that grows from the center, with a new shape, spoke count and difficulty in each day’s puzzle. It is in beta, so expect changes.
Chess training · web
Blindfold Chess Beta
Play blindfold chess against the AI or a friend, and build your board vision with lessons, puzzles and drills. It is in beta, so expect changes.
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