Expert Star Battle answer — October 10, 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: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 5, column 5).
3. 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 5).
4. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 5, column 3).
5. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 9, column 9).
6. Clump analysis (Region 9): candidate clumps can only just supply the remaining stars (row 3, column 2).
7. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 4).
8. Mark 3 cells adjacent to stars as X (row 4, column 3).
9. Three candidates with two adjacent: Isolated candidate must hold a star (row 4, column 2).
10. Mark 3 cells adjacent to stars as X (row 3, column 1).
11. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 1, column 2).
12. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 3).
13. Mark 4 cells adjacent to stars as X (row 1, column 4).
14. Generalized counting (columns 1-2): region star limits exclude these cells (row 9, column 3).
15. Triple analysis (Region 3 + Region 1 + Column 6): every legal combination of their stars rules these cells out (row 1, column 6).
16. Triple analysis (Region 9 + Region 5 + Row 7): every legal combination of their stars rules these cells out (row 7, column 7).
17. Triple analysis (Row 9 + Row 10 + Region 4): every legal combination of their stars rules these cells out (row 10, column 9).
18. Deep lookahead: Placing star here leads to contradiction - stars at R3C8 and R3C9 would touch (row 1, column 7).
19. Triple analysis (Region 3 + Column 7 + Region 5): every legal combination of their stars rules these cells out (row 9, column 6).
20. Quad analysis (Column 7 + Region 8 + Region 6 + Column 8): every legal combination of their stars rules these cells out (row 7, column 9).
21. Deep lookahead: Placing star here leads to contradiction - Column 8 would only have room for 0 of the 1 star it still needs (row 2, column 5).
22. Deep lookahead: Placing star here leads to contradiction - stars at R6C6 and R7C5 would touch (row 1, column 10).
23. Deep lookahead: Placing star here leads to contradiction - columns 4-5 can only hold 4 stars but the regions there would be forced to place 5 (row 3, column 6).
24. Composite container (columns 7-10): Regions 2, 6 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 8 stars - a star on these cells would crowd them out (row 9, column 8).
25. Generalized counting (rows 9-10): region star limits exclude these cells (row 8, column 5).
26. Deep lookahead: Placing star here leads to contradiction - Region 9 would end up with more than 2 stars (row 2, column 8).
27. Triple analysis (Column 7 + Region 6 + Column 8): every legal combination of their stars rules these cells out (row 5, column 9).
28. Deep lookahead: Placing star here leads to contradiction - Column 7 would only have room for 0 of the 1 star it still needs (row 1, column 1).
29. Region completion: 1 star needed, 1 candidate (row 2, column 1).
30. Deep lookahead: Placing star here leads to contradiction - Column 7 would only have room for 0 of the 1 star it still needs (row 2, column 10).
31. Quad analysis (Row 2 + Row 3 + Column 9 + Region 6): every legal combination of their stars rules these cells out (row 4, column 9).
32. Deep lookahead: Placing star here leads to contradiction - Region 8 would only have room for 0 of the 1 star it still needs (row 3, column 8).
33. Quad analysis (Region 3 + Region 5 + Region 6 + Column 6): every legal combination of their stars rules these cells out (row 4, column 6).
34. Quad analysis (Row 4 + Row 5 + Column 9 + Region 2): every legal combination of their stars rules these cells out (row 7, column 8).
35. Triple analysis (Region 3 + Row 5 + Region 5): every legal combination of their stars rules these cells out (row 5, column 8).
36. Composite container (rows 5-10): Regions 3, 4, 5, 7, 8 and 9 are confined here, so the leftover cells owe exactly 1 of the band's 12 stars - a star on these cells would crowd them out (row 6, column 10).
37. Quad analysis (Row 2 + Region 6 + Column 8 + Column 7): every legal combination of their stars rules these cells out (row 2, column 9).
38. Triple analysis (Region 3 + Region 5 + Region 6): every legal combination of their stars rules these cells out (row 7, column 6).
39. Clump analysis (Row 7): candidate clumps can only just supply the remaining stars (row 6, column 2).
40. Triple analysis (Row 6 + Column 1 + Row 7): every legal combination of their stars rules these cells out (row 8, column 1).
41. Squeeze (rows 8-9): the band's clumps can only just fit its stars (row 10, column 1).
42. Deep lookahead: Placing star here leads to contradiction - stars at R4C7 and R5C6 would touch (row 1, column 9).
43. Squeeze (columns 9-10): the band's clumps can only just fit its stars (row 9, column 10).
44. Three candidates with two adjacent: Isolated candidate must hold a star (row 10, column 10).
45. Clump analysis (Row 9): each clump must supply its full share of stars (row 9, column 5).
46. Mark 4 cells adjacent to stars as X (row 8, column 6).
47. Clump analysis (Row 8): each clump must supply its full share of stars (row 8, column 7).
48. Clump analysis (Column 6): candidate clumps can only just supply the remaining stars (row 2, column 7).
49. Row completion: 1 star needed, 1 candidate (row 2, column 6).
50. Mark 2 cells adjacent to stars as X (row 1, column 5).
51. Region completion: 1 star needed, 1 candidate (row 3, column 4).
52. Row completion: 1 star needed, 1 candidate (row 1, column 8).
53. Column 4 complete: Mark 1 remaining cell as X (row 7, column 4).
54. Region completion: 1 star needed, 1 candidate (row 7, column 3).
55. Mark 1 cell adjacent to stars as X (row 7, column 2).
56. Column completion: 1 star needed, 1 candidate (row 9, column 2).
57. Mark 2 cells adjacent to stars as X (row 9, column 1).
58. Column completion: 1 star needed, 1 candidate (row 7, column 5).
59. Mark 1 cell adjacent to stars as X (row 6, column 6).
60. Region completion: 1 star needed, 1 candidate (row 5, column 6).
61. Mark 1 cell adjacent to stars as X (row 4, column 7).
62. Region complete: Mark 1 remaining cell as X (row 6, column 8).
63. Region completion: 1 star needed, 1 candidate (row 6, column 9).
64. Mark 1 cell adjacent to stars as X (row 5, column 10).
65. Row completion: 1 star needed, 1 candidate (row 4, column 8).
66. Mark 1 cell adjacent to stars as X (row 3, column 9).
67. Region completion: 1 star needed, 1 candidate (row 3, column 10).
68. Row completion: 1 star needed, 1 candidate (row 6, column 1).
69. Mark 1 cell adjacent to stars as X (row 7, column 1).
70. Column completion: 1 star needed, 1 candidate (row 10, column 7).
71. Mark 1 cell adjacent to stars as X (row 10, column 8).
72. Column completion: 1 star needed, 1 candidate (row 8, column 9).
73. Mark 1 cell adjacent to stars as X (row 8, column 10).
74. Solved! Every row, column, and region has its two stars, none touching.