2024-September 🍁 Happy Autumn! 🍂
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Challenging Killer Sudoku, Volume 20
Each booklet contains a collection of eight different puzzles, 1-per-page, with a page of answers in the back. The booklets are ordered by ascending difficulty -- the puzzles in book 100 are much harder than the puzzles in book 1. All these puzzles have a single unique solution.
These puzzles are in PDF format and need the Adobe Acrobat Reader to view or print.
You can also download all 800 of these puzzles, in the 4-per-page format ( with hints and answers, with answers but no hints, or with neither hints nor answers).
Want to save even more trees? Try the online version of these puzzles.
Here's a handy cheat-sheet of candidate cage sets that makes it easier to eliminate numbers.
Problems printing puzzles? Try these work-arounds.
- Book 1
- Book 2
- Book 3
- Book 4
- Book 5
- Book 6
- Book 7
- Book 8
- Book 9
- Book 10
- Book 11
- Book 12
- Book 13
- Book 14
- Book 15
- Book 16
- Book 17
- Book 18
- Book 19
- Book 20
- Book 21
- Book 22
- Book 23
- Book 24
- Book 25
- Book 26
- Book 27
- Book 28
- Book 29
- Book 30
- Book 31
- Book 32
- Book 33
- Book 34
- Book 35
- Book 36
- Book 37
- Book 38
- Book 39
- Book 40
- Book 41
- Book 42
- Book 43
- Book 44
- Book 45
- Book 46
- Book 47
- Book 48
- Book 49
- Book 50
- Book 51
- Book 52
- Book 53
- Book 54
- Book 55
- Book 56
- Book 57
- Book 58
- Book 59
- Book 60
- Book 61
- Book 62
- Book 63
- Book 64
- Book 65
- Book 66
- Book 67
- Book 68
- Book 69
- Book 70
- Book 71
- Book 72
- Book 73
- Book 74
- Book 75
- Book 76
- Book 77
- Book 78
- Book 79
- Book 80
- Book 81
- Book 82
- Book 83
- Book 84
- Book 85
- Book 86
- Book 87
- Book 88
- Book 89
- Book 90
- Book 91
- Book 92
- Book 93
- Book 94
- Book 95
- Book 96
- Book 97
- Book 98
- Book 99
- Book 100
Out of challenging puzzles? Here's 800 more!.