1. Fill the Grid

Place numbers in every empty cell. Each cell belongs to a colored region.

2. Region Rule

Each colored region of size N must contain the numbers 1 through N, each exactly once.

3. Row & Column Rule

Each row and each column must contain unique numbers — no repeats allowed.

Tips

• Use Notes mode to mark possible candidates
• Look for cells where only one number fits
• Small regions are great starting points
• Check region AND row/column constraints together