Normal sudoku rules apply. Each grey line is a bulb-less thermometer. Along a thermometer, digits must increase from the bulb to the tip. The solver must deduce where each thermometer's bulb is - it will always be at one end of the line.
Normal sudoku rules apply. Each grey line is a bulb-less thermometer. Along a thermometer, digits must increase from the bulb to the tip. The solver must deduce where each thermometer's bulb is - it will always be at one end of the line.