Expert Star Battle answer — September 28, 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. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 2, column 5).
4. Clump analysis (Region 5): candidate clumps can only just supply the remaining stars (row 5, column 6).
5. Composite container (columns 1-5): Regions 1, 3 and 7 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 8, column 4).
6. Composite container (columns 1-6): Regions 1, 3, 6 and 7 are confined here, so the leftover cells owe exactly 4 of the band's 12 stars - a star on these cells would crowd them out (row 2, column 3).
7. Triple analysis (Region 3 + Column 2 + Region 1): every legal combination of their stars rules these cells out (row 5, column 3).
8. Triple analysis (Region 4 + Region 2 + Row 1): every legal combination of their stars rules these cells out (row 1, column 1).
9. Triple analysis (Region 5 + Region 8 + Column 8): every legal combination of their stars rules these cells out (row 3, column 7).
10. Deep lookahead: Placing star here leads to contradiction - Column 6 would only have room for 0 of the 1 star it still needs (row 1, column 7).
11. Deep lookahead: Placing star here leads to contradiction - stars at R5C7 and R6C7 would touch (row 2, column 4).
12. Squeeze (rows 2-3): the band's clumps can only just fit its stars (row 4, column 4).
13. Joint analysis (Region 3 + Region 1): every legal combination of their stars rules these cells out (row 7, column 2).
14. Triple analysis (Row 4 + Row 5 + Region 1): every legal combination of their stars rules these cells out (row 6, column 5).
15. Deep lookahead: Placing star here leads to contradiction - Region 1 would end up with more than 2 stars (row 1, column 6).
16. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 2, column 8).
17. Composite container (columns 1-6): Regions 1, 2, 3, 6 and 7 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 3, column 5).
18. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 5, column 2).
19. Crowding (Column 5): a star here would leave too little room for its 2 remaining stars (row 8, column 6).
20. Squeeze (rows 2-3): each clump in the band must supply its full share of stars (row 3, column 4).
21. Mark 1 cell adjacent to stars as X (row 4, column 3).
22. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 2, column 2).
23. Squeeze (rows 3-4): each clump in the band must supply its full share of stars (row 4, column 6).
24. Squeeze (rows 4-5): the band's clumps can only just fit its stars (row 1, column 4).
25. Column completion: 1 star needed, 1 candidate (row 5, column 4).
26. Mark 1 cell adjacent to stars as X (row 6, column 3).
27. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 5).
28. Mark 1 cell adjacent to stars as X (row 2, column 6).
29. Region completion: 1 star needed, 1 candidate (row 1, column 3).
30. Row 1 complete: Mark 2 remaining cells as X (row 1, column 8).
31. Region completion: 1 star needed, 1 candidate (row 2, column 7).
32. Mark 1 cell adjacent to stars as X (row 3, column 8).
33. Clump analysis (Column 3): candidate clumps can only just supply the remaining stars (row 8, column 2).
34. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 5, column 8).
35. Clump analysis (Region 5): candidate clumps can only just supply the remaining stars (row 7, column 8).
36. Crowding (Column 8): a star here would leave too little room for its 2 remaining stars (row 5, column 9).
37. Row completion: 1 star needed, 1 candidate (row 5, column 1).
38. Mark 4 cells adjacent to stars as X (row 4, column 1).
39. Column completion: 2 stars needed, 2 candidates (row 3, column 2).
40. Mark 2 cells adjacent to stars as X (row 2, column 1).
41. Row completion: 1 star needed, 1 candidate (row 2, column 9).
42. Mark 1 cell adjacent to stars as X (row 3, column 9).
43. Column completion: 1 star needed, 1 candidate (row 9, column 2).
44. Mark 4 cells adjacent to stars as X (row 8, column 1).
45. Region completion: 1 star needed, 1 candidate (row 7, column 1).
46. Region completion: 1 star needed, 1 candidate (row 9, column 5).
47. Mark 2 cells adjacent to stars as X (row 8, column 5).
48. Row completion: 2 stars needed, 2 candidates (row 8, column 7).
49. Mark 4 cells adjacent to stars as X (row 7, column 6).
50. Row completion: 1 star needed, 1 candidate (row 8, column 9).
51. Mark 2 cells adjacent to stars as X (row 7, column 9).
52. Column completion: 1 star needed, 1 candidate (row 7, column 3).
53. Row 7 complete: Mark 1 remaining cells as X (row 7, column 5).
54. Region completion: 1 star needed, 1 candidate (row 6, column 6).
55. Mark 1 cell adjacent to stars as X (row 6, column 7).
56. Column completion: 2 stars needed, 2 candidates (row 4, column 8).
57. Mark 1 cell adjacent to stars as X (row 4, column 9).
58. Column completion: 1 star needed, 1 candidate (row 6, column 8).
59. Mark 1 cell adjacent to stars as X (row 6, column 9).
60. Solved! Every row, column, and region has its two stars, none touching.