Isobars
by FullDeck and Missing a Few Cards Open on SudokuPad
GAS
- Kropki dots
- Same-class lines
- Isotropic
- Kropki difference
The brief
Normal sudoku constraints: every row, column, and box must contain a complete set of the digits 1-9. Kropki pairs: cells separated by a white dot form a consecutive pairs. Not all possible dots are given. Isobars (blue lines) have the same pressure along the entire line: either all the digits are low {1,2,3}, all the digits are middle {4, 5, 6} or all the digits are high {7, 8, 9}.