Hourglasses
- Kropki dots
- Between lines
The brief
Normal sudoku rules apply.
Digits on gray between lines must be between the digits in the attached circles. Digits in the circles of the between lines must be equal to their row, column, or box number.
Adjacent digits along an orange line must differ by at least 4.
Digits separated by a grain of sand (white dot) must be consecutive. Not all dots are given.