Fill every empty hexagon with a number from 1-7 so that no number repeats on any of the three axes.
The One Simple Rule
No Duplicates on Any Axis
Each hexagon belongs to three axes. No number can appear twice on the same axis.
Important: You do NOT need every number 1-7 on each axis — you just can't have duplicates!
The Three Axes
Every hexagon sits at the intersection of three lines:
Horizontal →
Same row
Diagonal ↘
Same column index
Diagonal ↙
Row + Column = constant
The Grid
The puzzle uses a 7×7 parallelogram of hexagons (49 cells total). Each row has 7 cells. Diagonals vary in length from 1 to 7 cells.
Solving Techniques
Naked Singles
When a cell can only contain one possible value because all other numbers would create a duplicate on one of its three axes, fill it in!
Using Pencil Marks
Use pencil marks to track which numbers are still possible in each cell. Click Auto Pencil to fill them in automatically, then look for cells with only one candidate.
💡 Tip: After placing a number, the game automatically removes that number from pencil marks in related cells. This can reveal new naked singles!
Controls
Mouse/Touch
Click a cell to select it
Normal mode: Click numbers to fill the cell
Pencil mode: Click numbers to toggle pencil marks
Keyboard
1-7 — Enter number (or toggle pencil mark in pencil mode)
Shift + number — Toggle pencil mark (in any mode)
Arrow keys — Navigate between cells
Space — Pause/Resume game
H — Get a hint
P — Toggle between Normal and Pencil mode
Backspace — Clear cell
Shift + Backspace — Clear cell's pencil marks
Escape — Deselect cell
Buttons
⏸️ Pause: Pause the timer and hide the puzzle
💡 Hint: Highlights a cell you can solve next
Auto Pencil: Fills all possible values for empty cells
Clear Pencils: Removes all pencil marks
Reset: Start the puzzle over
Solution: Reveal the answer
Filters
Size: Filter puzzles by grid size (currently only 7×7)
Difficulty: Filter by Easy, Medium, or Hard
Visual Indicators
Red numbers — Clues (fixed, cannot be changed)
Green cells — Clue cells
Blue highlight — Selected cell
Yellow highlight — Hinted cell
Pink/red cells — Conflict detected (duplicate on an axis)