Expert Star Battle answer — December 19, 2025

Full written solution

Every deduction from the walkthrough above, in order. Each technique is explained in the Star Battle strategy guide.

1. Starting position — the grid is split into regions (bold outlines). Each row, column, and region needs exactly two stars, and no two stars may touch.
2. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 2, column 4).
3. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 4).
4. Mark 4 cells adjacent to stars as X (row 1, column 3).
5. Two-option rule: Cell adjacent to both candidates (row 4, column 3).
6. Two-option rule: Cell adjacent to both candidates (row 4, column 4).
7. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 5, column 8).
8. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 6, column 4).
9. Clump analysis (Column 1): candidate clumps can only just supply the remaining stars (row 1, column 2).
10. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 8, column 8).
11. Clump analysis (Region 7): candidate clumps can only just supply the remaining stars (row 3, column 8).
12. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 6, column 3).
13. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 8, column 3).
14. Squeeze (rows 1-2): the band's clumps can only just fit its stars (row 3, column 5).
15. Clump analysis (Row 3): each clump must supply its full share of stars (row 3, column 1).
16. Mark 3 cells adjacent to stars as X (row 2, column 1).
17. Clump analysis (Row 2): candidate clumps can only just supply the remaining stars (row 1, column 6).
18. Row completion: 1 star needed, 1 candidate (row 1, column 1).
19. Region complete: Mark 5 remaining cells as X (row 5, column 1).
20. Clump analysis (Column 6): candidate clumps can only just supply the remaining stars (row 8, column 5).
21. Clump analysis (Column 5): candidate clumps can only just supply the remaining stars (row 5, column 4).
22. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 3).
23. Mark 2 cells adjacent to stars as X (row 5, column 2).
24. Region completion: 2 stars needed, 2 candidates (row 4, column 5).
25. Mark 2 cells adjacent to stars as X (row 3, column 4).
26. Region completion: 1 star needed, 1 candidate (row 3, column 3).
27. Region completion: 1 star needed, 1 candidate (row 7, column 2).
28. Mark 1 cell adjacent to stars as X (row 7, column 3).
29. Column completion: 1 star needed, 1 candidate (row 9, column 2).
30. Mark 1 cell adjacent to stars as X (row 9, column 3).
31. Two last candidates (row 5): Eliminate 2 cells adjacent to both (row 4, column 8).
32. Clump analysis (Column 6): each clump must supply its full share of stars (row 2, column 6).
33. Mark 1 cell adjacent to stars as X (row 2, column 7).
34. Clump analysis (Column 7): candidate clumps can only just supply the remaining stars (row 7, column 8).
35. Column completion: 2 stars needed, 2 candidates (row 2, column 8).
36. Mark 1 cell adjacent to stars as X (row 2, column 9).
37. Column completion: 1 star needed, 1 candidate (row 9, column 8).
38. Mark 2 cells adjacent to stars as X (row 8, column 9).
39. Row completion: 2 stars needed, 2 candidates (row 8, column 4).
40. Mark 2 cells adjacent to stars as X (row 7, column 5).
41. Region completion: 1 star needed, 1 candidate (row 6, column 5).
42. Row completion: 1 star needed, 1 candidate (row 8, column 6).
43. Mark 2 cells adjacent to stars as X (row 7, column 7).
44. Row completion: 1 star needed, 1 candidate (row 7, column 9).
45. Mark 1 cell adjacent to stars as X (row 6, column 9).
46. Region completion: 1 star needed, 1 candidate (row 5, column 9).
47. Mark 1 cell adjacent to stars as X (row 4, column 9).
48. Row completion: 1 star needed, 1 candidate (row 4, column 7).
49. Mark 1 cell adjacent to stars as X (row 5, column 7).
50. Region completion: 1 star needed, 1 candidate (row 6, column 7).
51. Solved! Every row, column, and region has its two stars, none touching.