Normal Sudoku rules apply.
X-Sudoku rules apply. Digits may not repeat on either diagonal.
Entropy rules apply. Every 2x2 square in the grid must contain a low digit (1/2/3), a middle digit (4/5/6) and a high digit (7/8/9).
Keypad Knight lines: Indigo lines connect digits a knight's move apart on a phone keypad (e.g. 1 must connect to 6 or 8). Digits may repeat if allowed by other rules.
Kropki rules: The black Kropki dot separates two digits with a 2:1 ratio. Not all Kropki dots are given.
Solution code: Row 1 followed by column 9 (18 digits, left to right, top to bottom, no spaces/commas).
on 24. March 2022, 14:56 by drbs
Sehr schönes Rätsel.
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Jeremy Dover: Danke sehr!!