A New Sudoku Layout with 81 Uniquely Shaped Cells

March 12, 2025・5 minute read Something productive finally came from my daily Sudoku habit: I invented a new type of puzzle that I call “Cracked Sudoku”. You can play it here. It looks like cracked dirt, see? Even though it looks weird, the rules should feel familiar to Sudoku fans: Fill the cells with numbers 1-9 without repeating numbers in a dark-outlined area or along a run. (Runs are shown when a cell is selected) Give it a try: Play Cracked Sudoku Designing the Ruleset Those of you with a life may be unaware that the past 10 years have seen an explosion of alternative Sudoku rules: German Whisper Lines, Dutch flat mates, Killer cages, Yin-yang (My favorite), Fog-of-war, Sum arrows, Even & Odd squares, Thermometers, Black dots, White dots, Jigsaw Sudo, Renban lines, Nabner lines, Star Battle, Masyu loop, Inequality signs, Region sum lines Whew. Despite all the innovation in rules, there has been comparatively little innovation in layout. Pretty much all Sudoku use a 9x9 ... Read full article.