Expert Star Battle answer — September 15, 2026

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: This position would block too many candidates (row 8, column 8).
3. Blocking rule: This position would block too many candidates (row 1, column 4).
4. Blocking rule: This position would block too many candidates (row 2, column 4).
5. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 3).
6. Mark 3 cells adjacent to stars as X (row 1, column 2).
7. Two-option rule: Cell adjacent to both candidates (row 1, column 6).
8. Two-option rule: Cell adjacent to both candidates (row 2, column 6).
9. Blocking rule: This position would block too many candidates (row 4, column 5).
10. Blocking rule: This position would block too many candidates (row 2, column 8).
11. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 4, column 2).
12. Clump analysis (Region 6): candidate clumps can only just supply the remaining stars (row 7, column 2).
13. Clump analysis (Region 7): candidate clumps can only just supply the remaining stars (row 4, column 6).
14. Generalized counting (columns 7-9): region star limits exclude these cells (row 9, column 7).
15. Composite container (columns 2-6): Regions 3, 5, 6 and 7 are confined here, so the leftover cells owe exactly 2 of the band's 10 stars - a star on these cells would crowd them out (row 6, column 3).
16. Joint analysis (Row 1 + Region 9): every legal combination of their stars rules these cells out (row 3, column 8).
17. Lookahead: Placing star here leads to contradiction - rows 1-3 can only hold 6 stars but the regions there would be forced to place 7 (row 5, column 4).
18. Joint analysis (Region 6 + Row 5): every legal combination of their stars rules these cells out (row 6, column 6).
19. Composite container (columns 4-6): Regions 5 and 7 are confined here, so the leftover cells owe exactly 3 of the band's 6 stars - a star on these cells would crowd them out (row 8, column 7).
20. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 6, column 7).
21. Joint analysis (Region 6 + Row 6): every legal combination of their stars rules these cells out (row 5, column 1).
22. Joint analysis (Row 8 + Row 7): every legal combination of their stars rules these cells out (row 9, column 2).
23. Crowding (Column 2): a star here would leave too little room for its 2 remaining stars (row 7, column 3).
24. Clump analysis (Region 6): each clump must supply its full share of stars (row 6, column 2).
25. Mark 2 cells adjacent to stars as X (row 5, column 3).
26. Clump analysis (Row 5): candidate clumps can only just supply the remaining stars (row 4, column 8).
27. Squeeze (rows 5-6): the band's clumps can only just fit its stars (row 4, column 7).
28. Squeeze (rows 6-7): the band's clumps can only just fit its stars (row 8, column 6).
29. Squeeze (columns 3-4): the band's clumps can only just fit its stars (row 6, column 5).
30. Two-option rule: Cell adjacent to both candidates (row 8, column 3).
31. Squeeze (rows 7-8): the band's clumps can only just fit its stars (row 9, column 1).
32. Composite container (columns 2-6): Regions 3, 5, 6 and 7 are confined here, so the leftover cells owe exactly 2 of the band's 10 stars - a star on these cells would crowd them out (row 5, column 5).
33. Region completion: 1 star needed, 1 candidate (row 8, column 4).
34. Mark 3 cells adjacent to stars as X (row 9, column 3).
35. Three candidates in a column: Middle cell can't hold a star (row 2, column 5).
36. Region completion: 1 star needed, 1 candidate (row 1, column 5).
37. Row 1 complete: Mark 4 remaining cells as X (row 1, column 1).
38. Column completion: 1 star needed, 1 candidate (row 3, column 5).
39. Mark 3 cells adjacent to stars as X (row 3, column 4).
40. Region completion: 1 star needed, 1 candidate (row 5, column 6).
41. Mark 1 cell adjacent to stars as X (row 5, column 7).
42. Column completion: 1 star needed, 1 candidate (row 6, column 4).
43. Row 6 complete: Mark 1 remaining cells as X (row 6, column 9).
44. Three candidates with two adjacent: Isolated candidate must hold a star (row 2, column 9).
45. Mark 1 cell adjacent to stars as X (row 3, column 9).
46. Blocking rule: This position would block too many candidates (row 3, column 2).
47. Column completion: 1 star needed, 1 candidate (row 8, column 2).
48. Mark 1 cell adjacent to stars as X (row 8, column 1).
49. Region completion: 1 star needed, 1 candidate (row 4, column 1).
50. Mark 1 cell adjacent to stars as X (row 3, column 1).
51. Row 8 complete: Mark 1 remaining cells as X (row 8, column 9).
52. Column completion: 1 star needed, 1 candidate (row 2, column 1).
53. Row 2 complete: Mark 1 remaining cells as X (row 2, column 7).
54. Region completion: 1 star needed, 1 candidate (row 3, column 7).
55. Row 3 complete: Mark 1 remaining cells as X (row 3, column 3).
56. Region completion: 1 star needed, 1 candidate (row 4, column 3).
57. Row 4 complete: Mark 1 remaining cells as X (row 4, column 9).
58. Column completion: 1 star needed, 1 candidate (row 7, column 7).
59. Mark 2 cells adjacent to stars as X (row 7, column 6).
60. Region completion: 1 star needed, 1 candidate (row 9, column 6).
61. Row completion: 1 star needed, 1 candidate (row 7, column 9).
62. Column completion: 2 stars needed, 2 candidates (row 5, column 8).
63. Mark 1 cell adjacent to stars as X (row 5, column 9).
64. Column completion: 1 star needed, 1 candidate (row 9, column 8).
65. Mark 1 cell adjacent to stars as X (row 9, column 9).
66. Solved! Every row, column, and region has its two stars, none touching.