Puzzle rules & guides
How every puzzle in the library works, and how to get better at it. Pick a category, or jump straight to a puzzle — each one opens its rules, with its strategy guides a line below.
Games
Classic puzzle games with number placement and logic.
Logic
Deductive reasoning, pattern recognition, and codebreaking.
- Logic Grid PuzzlesUse elimination grids to match categories by logic.Guides →
- Pattern PuzzlesSpot the rule in sequences, matrices, and odd-one-out sets.Guides →
- Deduction PuzzlesSolve mysteries by reading clues and ruling out suspects.Guides →
- Red-HandedPlace everyone, then find the one account that cannot be true.Guides →
- CryptogramDecode a substitution cipher to reveal a quote.Guides →
Math
Mathematical riddles, brain teasers, and number challenges.
Words
Word-based puzzles: scrambles, searches, and ciphers.
Grid
Grid-based puzzles with spatial reasoning and constraints.
- KakuroFill number sums into a crossword-style grid.Guides →
- SkyscrapersDeduce building heights from edge visibility clues.Guides →
- BinairoFill a grid with 0s and 1s following three simple rules.Guides →
- Star BattlePlace stars so each row, column, and region has the right count.Guides →
- Light Up (Akari)Place light bulbs to illuminate every cell without conflicts.Guides →
- SuguruFill numbered groups so no identical digits touch.Guides →
- SlitherlinkDraw a single loop on grid edges guided by number clues.Guides →
- HashiConnect islands with bridges to form a single network.Guides →
- NurikabeGuides →
- ShikakuGuides →
- AquariumGuides →
- HitoriGuides →
Sudoku Puzzles
Classic Sudoku and its variants: Killer, Samurai, Jigsaw, KenKen, and Futoshiki.
- SudokuFill a 9×9 grid so every row, column, and box contains 1–9.Guides →
- Killer SudokuSudoku with cage sums — no repeated digits in any cage.Guides →
- Samurai SudokuFive overlapping 9×9 Sudoku grids — solve them all at once.Guides →
- Jigsaw SudokuSudoku with irregular regions instead of standard 3×3 boxes.Guides →
- KenKenCombine arithmetic and Latin square logic in caged grids.Guides →
- FutoshikiPlace digits with inequality constraints between cells.Guides →
Want to be shown rather than told? Walk through a puzzle, move by move.