Anti-Knight Sudoku
No two cells a knight's move apart may contain the same digit
Anti-Knight Sudoku is fully playable. Choose a difficulty and start solving.
No digit may repeat a knight's L-shaped jump away — a long-range rule that ties together boxes that ordinary scanning treats as strangers. You will spend the solve mapping each placement's possible landing squares. Harder than it sounds; forgetting one knight reach is the textbook mistake.
For the complete rules, worked examples and solving techniques, read the full How to Play Anti-Knight Sudoku guide.
Like all Sudoku variants, Anti-Knight Sudoku builds on the classic 9×9 foundation. Every row, column, and 3×3 box must contain each digit from 1 to 9 exactly once. The variant constraint is added on top of these standard rules, never replacing them.
If you're new to Sudoku, start by learning the basic rules and techniques before attempting variants.
Techniques Useful for This Variant
| Technique | How it applies |
|---|---|
| Pencil Marks / Notes | Essential for tracking candidates alongside the variant constraint |
| Obvious Singles | Cells narrowed to one candidate by the combined constraints |
| Hidden Singles | Digits with only one valid cell in a unit after variant elimination |
| Pairs and Triples | Locked candidates exposed by the additional constraint |