Expert Star Battle answer — September 26, 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 2, column 2).
3. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 8, column 7).
4. Clump analysis (Region 7): candidate clumps can only just supply the remaining stars (row 5, column 9).
5. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 1, column 2).
6. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 2, column 6).
7. Generalized counting (columns 8-10): region star limits exclude these cells (row 2, column 8).
8. Clump analysis (Region 6): candidate clumps can only just supply the remaining stars (row 8, column 4).
9. Composite container (rows 1-8): Regions 1, 2, 3, 5, 6, 7 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 16 stars - a star on these cells would crowd them out (row 7, column 9).
10. Composite container (columns 1-7): Regions 2, 3, 5, 6, 8 and 9 are confined here, so the leftover cells owe exactly 2 of the band's 14 stars - a star on these cells would crowd them out (row 8, column 8).
11. Three candidates with two adjacent: Isolated candidate must hold a star (row 9, column 7).
12. Two-option rule: Cell adjacent to both candidates (row 8, column 10).
13. Two-option rule: Cell adjacent to both candidates (row 9, column 10).
14. Blocking rule: This position would block too many candidates (row 9, column 2).
15. Composite container (rows 1-8): Regions 1, 2, 3, 5, 6, 7 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 16 stars - a star on these cells would crowd them out (row 7, column 1).
16. Lookahead: Placing star here leads to contradiction - row 1 can only hold 2 stars but the regions there would be forced to place 3 (row 1, column 3).
17. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 2, column 5).
18. Generalized counting (columns 6-7): region star limits exclude these cells (row 5, column 6).
19. Generalized counting (columns 1-3): region star limits exclude these cells (row 5, column 4).
20. Squeeze (columns 4-5): each clump in the band must supply its full share of stars (row 10, column 5).
21. Joint analysis (Region 8 + Row 2): every legal combination of their stars rules these cells out (row 1, column 4).
22. Crowding (Column 4): a star here would leave too little room for its 2 remaining stars (row 3, column 5).
23. Lookahead: Placing star here leads to contradiction - stars at R2C3 and R2C4 would touch (row 4, column 3).
24. Joint analysis (Row 2 + Row 3): every legal combination of their stars rules these cells out (row 4, column 7).
25. Joint analysis (Row 5 + Row 6): every legal combination of their stars rules these cells out (row 6, column 2).
26. Joint analysis (Region 7 + Row 5): every legal combination of their stars rules these cells out (row 4, column 2).
27. Joint analysis (Region 3 + Region 8): every legal combination of their stars rules these cells out (row 1, column 8).
28. Blocking rule: This position would block too many candidates (row 3, column 9).
29. Clump analysis (Column 8): candidate clumps can only just supply the remaining stars (row 3, column 7).
30. Clump analysis (Column 8): each clump must supply its full share of stars (row 6, column 8).
31. Mark 4 cells adjacent to stars as X (row 5, column 7).
32. Column completion: 1 star needed, 1 candidate (row 1, column 7).
33. Mark 1 cell adjacent to stars as X (row 1, column 6).
34. Blocking rule: This position would block too many candidates (row 4, column 5).
35. Three candidates with two adjacent: Isolated candidate must hold a star (row 4, column 4).
36. Mark 1 cell adjacent to stars as X (row 5, column 3).
37. Blocking rule: This position would block too many candidates (row 7, column 5).
38. Clump analysis (Row 5): candidate clumps can only just supply the remaining stars (row 4, column 1).
39. Region completion: 1 star needed, 1 candidate (row 5, column 10).
40. Squeeze (rows 6-7): the band's clumps can only just fit its stars (row 10, column 9).
41. Region completion: 1 star needed, 1 candidate (row 7, column 10).
42. Mark 1 cell adjacent to stars as X (row 8, column 9).
43. Region completion: 1 star needed, 1 candidate (row 9, column 9).
44. Row 9 complete: Mark 1 remaining cells as X (row 9, column 3).
45. Column completion: 1 star needed, 1 candidate (row 2, column 9).
46. Mark 1 cell adjacent to stars as X (row 3, column 8).
47. Region completion: 1 star needed, 1 candidate (row 4, column 8).
48. Row 4 complete: Mark 1 remaining cells as X (row 4, column 6).
49. Region completion: 1 star needed, 1 candidate (row 3, column 6).
50. Two last candidates (row 3): Eliminate 1 cell adjacent to both (row 2, column 1).
51. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 1).
52. Row 1 complete: Mark 1 remaining cells as X (row 1, column 5).
53. Region completion: 1 star needed, 1 candidate (row 2, column 4).
54. Mark 1 cell adjacent to stars as X (row 2, column 3).
55. Region completion: 1 star needed, 1 candidate (row 3, column 2).
56. Mark 1 cell adjacent to stars as X (row 3, column 1).
57. Column 4 complete: Mark 1 remaining cells as X (row 7, column 4).
58. Column completion: 1 star needed, 1 candidate (row 8, column 5).
59. Mark 1 cell adjacent to stars as X (row 7, column 6).
60. Region completion: 1 star needed, 1 candidate (row 6, column 6).
61. Row 6 complete: Mark 1 remaining cells as X (row 6, column 3).
62. Row completion: 1 star needed, 1 candidate (row 7, column 3).
63. Mark 2 cells adjacent to stars as X (row 8, column 2).
64. Row completion: 1 star needed, 1 candidate (row 8, column 1).
65. Column 1 complete: Mark 2 remaining cells as X (row 5, column 1).
66. Region completion: 1 star needed, 1 candidate (row 5, column 2).
67. Column 2 complete: Mark 1 remaining cells as X (row 10, column 2).
68. Region completion: 1 star needed, 1 candidate (row 10, column 3).
69. Solved! Every row, column, and region has its two stars, none touching.