The variants
Every rule in the book.
Same rules. Different mysteries. Pick a variant to see its rules and every open case that uses it.
- Killer Same rules. Extra sums. A deeper mystery. 459 cases
- Kropki Two kinds of dot. Every one a clue. 239 cases
- Thermo The temperature only rises. 165 cases
- Arrow Follow the arrow to the total. 150 cases
- Renban A run of digits, in any order. 98 cases
- Kropki ratio One digit is always double the other. 96 cases
- German whisper Neighbours keep their distance. 91 cases
- Little killer Sums from outside the frame. 88 cases
- Modular Remainders tell the story. 88 cases
- Quadruple Four cells, a few digits, no locations. 73 cases
- Anti-knight Watch the knight. 55 cases
- Whisper 5 Neighbours keep their distance. 55 cases
- Region sum Every box pays the same toll. 41 cases
- Whisper 4 A little less distance, a lot more options. 41 cases
- Diagonal sum 38 cases
- Consecutive Neighbours that sit side by side. 33 cases
- Dutch whisper A little less distance, a lot more options. 33 cases
- XV Roman numerals, modern mystery. 31 cases
- Entropic Low, middle, high. Always all three. 29 cases
- Zipper Fold the line in half. It adds up. 28 cases
- Kropki difference Neighbours that sit side by side. 25 cases
- Sandwich What lies between the 1 and the 9. 24 cases
- X-sum The first digit says how far to count. 23 cases
- Fog of war The grid reveals itself one clue at a time. 22 cases
- Skyscraper Count the buildings you can see. 16 cases
- Diagonal Two more lines to keep clean. 15 cases
- Between Caught between two circles. 13 cases
- Palindrome It reads the same both ways. 12 cases
- Anti-king No two alike, even diagonally. 10 cases
- Nabner No neighbours, near or far. 10 cases
- Slow thermo Rising, or holding steady. 10 cases
- Non-consecutive Neighbours never follow on. 9 cases
- Double arrow 8 cases
- Parity line Odd, even, odd, even. 8 cases
- Disjoint Same spot, every box, all different. 6 cases
- Even/odd 6 cases
- 1-5-9 5 cases
- Even 4 cases
- Outside 4 cases
- X10 3 cases
- XV (negative) 3 cases
- Arrowpill 3 cases
- Columnindex 3 cases
- Fortress 3 cases
- Lockout 3 cases
- Numbered rooms 3 cases
- Odd 3 cases
- Cage (no sum) 2 cases
- Isotropic 2 cases
- Kropki (negative) 2 cases
- Min max 2 cases
- Rowindex 2 cases
- Unimodular 2 cases
- V5 1 case
- X NEG 1 case
- Clone 1 case
- Extra region 1 case
- Global entropy 1 case
- Kropki ratio neg 1 case
- Runsums 1 case
- Whispers 5 1 case
