Hard Little Killer Sudoku
9
2
7
2
4
8
5
6
8
4
1
9
7
5
3
5
6
2
1
7
3
5
9
4
6
9
8
Diagonal Clues
↘
from (1,1):
57
(9 cells)
↘
from (1,2):
47
(8 cells)
↘
from (1,3):
34
(7 cells)
↘
from (1,4):
40
(6 cells)
↘
from (1,5):
15
(5 cells)
↘
from (1,6):
10
(4 cells)
↘
from (1,7):
18
(3 cells)
↘
from (1,8):
14
(2 cells)
↘
from (2,1):
33
(8 cells)
↘
from (3,1):
32
(7 cells)
↘
from (4,1):
33
(6 cells)
↘
from (5,1):
28
(5 cells)
↘
from (6,1):
15
(4 cells)
↘
from (7,1):
9
(3 cells)
↘
from (8,1):
14
(2 cells)
↙
from (1,2):
16
(2 cells)
↙
from (1,3):
8
(3 cells)
↙
from (1,4):
22
(4 cells)
↙
from (1,5):
26
(5 cells)
↙
from (1,6):
24
(6 cells)
↙
from (1,7):
36
(7 cells)
↙
from (1,8):
53
(8 cells)
↙
from (1,9):
42
(9 cells)
↙
from (2,9):
33
(8 cells)
↙
from (3,9):
27
(7 cells)
↙
from (4,9):
27
(6 cells)
↙
from (5,9):
32
(5 cells)
↙
from (6,9):
20
(4 cells)
↙
from (7,9):
15
(3 cells)
↙
from (8,9):
11
(2 cells)
How to play Little Killer Sudoku
Standard Sudoku rules apply. The clue list shows diagonal sums - Each entry gives the sum of all cells along that diagonal. The arrow direction (↘ or ↙) and starting cell are shown. Digits may repeat on a diagonal.
About Little Killer Sudoku
Difficulty
★★★★☆
4/5
Constraint Type
Outside Clues
Typical Givens
0–6 given digits
Avg. Solve (Medium)
28 min
Little Killer Sudoku places clues outside the grid along with a diagonal arrow. The arrow points to a diagonal stripe of cells, and the clue gives the sum of all digits along that diagonal. Unlike standard Killer Sudoku cages, digits CAN repeat on Little Killer diagonals as long as they don't violate the row/column/box rules. This makes the arithmetic different from standard cage solving.
Solving Techniques
| Technique | Description | Level |
|---|---|---|
| Diagonal Enumeration | For each clue, enumerate all combinations of N digits (allowing repeats, 1–9) that sum to the clue value. | Beginner |
| Repeating Digits Allowed | Unlike Killer cages, Little Killer diagonals can repeat digits as long as standard row/column/box uniqueness is preserved. | Beginner |
| Short Diagonal Logic | A 1-cell diagonal directly gives that cell's digit. A 2-cell diagonal with clue C has limited pairs — enumerate them immediately. | Intermediate |
| Cross-Diagonal Intersection | When two diagonals share a cell, the shared cell must satisfy both sum constraints simultaneously. | Advanced |
| Row/Column Interaction | A diagonal cell belongs to a row, column, and box — combine Little Killer sum constraints with standard uniqueness rules. | Intermediate |
Average Solve Time by Difficulty
Easy
14 min
Medium
28 min
Hard
55 min
Expert
88 min