Expert Star Battle answer — September 29, 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. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 3, column 2).
3. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 6, column 4).
4. Blocking rule: This position would block too many candidates (row 5, column 6).
5. Clump analysis (Region 9): candidate clumps can only just supply the remaining stars (row 6, column 8).
6. Clump analysis (Region 5): candidate clumps can only just supply the remaining stars (row 7, column 5).
7. Blocking rule: This position would block too many candidates (row 6, column 3).
8. Joint analysis (Region 5 + Row 6): every legal combination of their stars rules these cells out (row 7, column 6).
9. Joint analysis (Region 3 + Column 5): every legal combination of their stars rules these cells out (row 4, column 4).
10. Triple analysis (Region 3 + Region 7 + Row 7): every legal combination of their stars rules these cells out (row 8, column 3).
11. Triple analysis (Region 5 + Row 6 + Row 7): every legal combination of their stars rules these cells out (row 8, column 4).
12. Quad analysis (Region 7 + Column 6 + Column 5 + Region 8): every legal combination of their stars rules these cells out (row 3, column 7).
13. Deep lookahead: Placing star here leads to contradiction - stars at R8C7 and R9C8 would touch (row 2, column 7).
14. Triple analysis (Column 4 + Column 5 + Region 8): every legal combination of their stars rules these cells out (row 4, column 6).
15. Clump analysis (Region 7): candidate clumps can only just supply the remaining stars (row 5, column 8).
16. Generalized counting (columns 7-9): region star limits exclude these cells (row 9, column 7).
17. Deep lookahead: Placing star here leads to contradiction - Row 7 would only have room for 0 of the 1 star it still needs (row 1, column 1).
18. Triple analysis (Region 4 + Row 3 + Row 2): every legal combination of their stars rules these cells out (row 3, column 5).
19. Triple analysis (Column 6 + Region 7 + Column 5): every legal combination of their stars rules these cells out (row 5, column 4).
20. Composite container (rows 1-6): Regions 1, 4, 6, 7 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 12 stars - a star on these cells would crowd them out (row 5, column 2).
21. Triple analysis (Region 3 + Region 1 + Column 1): every legal combination of their stars rules these cells out (row 7, column 1).
22. Triple analysis (Region 5 + Region 2 + Row 8): every legal combination of their stars rules these cells out (row 9, column 2).
23. Joint analysis (Region 3 + Column 2): every legal combination of their stars rules these cells out (row 7, column 3).
24. Triple analysis (Region 5 + Row 7 + Row 6): every legal combination of their stars rules these cells out (row 5, column 5).
25. Composite container (rows 1-5): Regions 4, 6 and 8 are confined here, so the leftover cells owe exactly 4 of the band's 10 stars - a star on these cells would crowd them out (row 4, column 8).
26. Triple analysis (Region 3 + Region 7 + Row 5): every legal combination of their stars rules these cells out (row 6, column 2).
27. Clump analysis (Column 2): candidate clumps can only just supply the remaining stars (row 1, column 3).
28. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 9, column 1).
29. Three candidates with two adjacent: Isolated candidate must hold a star (row 9, column 4).
30. Mark 2 cells adjacent to stars as X (row 8, column 5).
31. Region completion: 1 star needed, 1 candidate (row 8, column 2).
32. Mark 1 cell adjacent to stars as X (row 7, column 2).
33. Region completion: 2 stars needed, 2 candidates (row 5, column 3).
34. Mark 1 cell adjacent to stars as X (row 4, column 3).
35. Region completion: 1 star needed, 1 candidate (row 7, column 4).
36. Mark 1 cell adjacent to stars as X (row 6, column 5).
37. Column completion: 1 star needed, 1 candidate (row 3, column 3).
38. Mark 3 cells adjacent to stars as X (row 2, column 2).
39. Column completion: 1 star needed, 1 candidate (row 1, column 2).
40. Column 4 complete: Mark 1 remaining cells as X (row 1, column 4).
41. Region completion: 1 star needed, 1 candidate (row 2, column 5).
42. Mark 4 cells adjacent to stars as X (row 1, column 5).
43. Region completion: 1 star needed, 1 candidate (row 4, column 5).
44. Column completion: 2 stars needed, 2 candidates (row 6, column 6).
45. Mark 3 cells adjacent to stars as X (row 5, column 7).
46. Region completion: 1 star needed, 1 candidate (row 4, column 7).
47. Mark 1 cell adjacent to stars as X (row 3, column 8).
48. Row 4 complete: Mark 2 remaining cells as X (row 4, column 1).
49. Column completion: 1 star needed, 1 candidate (row 8, column 6).
50. Mark 1 cell adjacent to stars as X (row 8, column 7).
51. Region completion: 1 star needed, 1 candidate (row 7, column 8).
52. Mark 3 cells adjacent to stars as X (row 6, column 9).
53. Row completion: 1 star needed, 1 candidate (row 6, column 1).
54. Mark 1 cell adjacent to stars as X (row 5, column 1).
55. Region completion: 1 star needed, 1 candidate (row 3, column 1).
56. Row 3 complete: Mark 1 remaining cells as X (row 3, column 9).
57. Row completion: 1 star needed, 1 candidate (row 5, column 9).
58. Column completion: 1 star needed, 1 candidate (row 1, column 7).
59. Mark 2 cells adjacent to stars as X (row 1, column 8).
60. Row 1 complete: Mark 1 remaining cells as X (row 1, column 9).
61. Region completion: 1 star needed, 1 candidate (row 2, column 9).
62. Column completion: 1 star needed, 1 candidate (row 9, column 8).
63. Mark 1 cell adjacent to stars as X (row 9, column 9).
64. Solved! Every row, column, and region has its two stars, none touching.