Expert Star Battle answer — August 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 2): candidate clumps can only just supply the remaining stars (row 2, column 5).
3. Clump analysis (Region 6): candidate clumps can only just supply the remaining stars (row 7, column 1).
4. Clump analysis (Region 9): candidate clumps can only just supply the remaining stars (row 5, column 1).
5. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 9, column 1).
6. Three candidates with two adjacent: Isolated candidate must hold a star (row 10, column 1).
7. Mark 1 cell adjacent to stars as X (row 9, column 2).
8. Region completion: 1 star needed, 1 candidate (row 8, column 2).
9. Mark 1 cell adjacent to stars as X (row 9, column 3).
10. Clump analysis (Region 10): candidate clumps can only just supply the remaining stars (row 9, column 9).
11. Squeeze (rows 9-10): the band's clumps can only just fit its stars (row 8, column 5).
12. Composite container (columns 1-3): Region 8 is confined here, so the leftover cells owe exactly 2 of the band's 6 stars - a star on these cells would crowd them out (row 5, column 4).
13. Composite container (columns 3-10): Regions 1, 2, 3, 4, 5, 7 and 10 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 2, column 2).
14. Lookahead: Placing star here leads to contradiction - row 6 can only hold 2 stars but the regions there would be forced to place 3 (row 6, column 5).
15. Joint analysis (Row 10 + Region 10): every legal combination of their stars rules these cells out (row 8, column 9).
16. Triple analysis (Region 10 + Region 7 + Column 10): every legal combination of their stars rules these cells out (row 9, column 8).
17. Deep lookahead: Placing star here leads to contradiction - stars at R3C3 and R4C3 would touch (row 1, column 6).
18. Deep lookahead: Placing star here leads to contradiction - stars at R3C3 and R4C3 would touch (row 1, column 8).
19. Deep lookahead: Placing star here leads to contradiction - Region 7 would only have room for 0 of the 1 star it still needs (row 2, column 9).
20. Deep lookahead: Placing star here leads to contradiction - Row 2 would only have room for 1 of the 2 stars it still needs (row 4, column 2).
21. Deep lookahead: Placing star here leads to contradiction - Row 5 would only have room for 0 of the 1 star it still needs (row 1, column 9).
22. Triple analysis (Column 9 + Column 8 + Region 7): every legal combination of their stars rules these cells out (row 10, column 10).
23. Quad analysis (Region 10 + Column 9 + Region 7 + Column 10): every legal combination of their stars rules these cells out (row 4, column 10).
24. Triple analysis (Region 1 + Row 5 + Region 4): every legal combination of their stars rules these cells out (row 4, column 4).
25. Quad analysis (Region 1 + Row 5 + Column 6 + Region 4): every legal combination of their stars rules these cells out (row 8, column 7).
26. Deep lookahead: Placing star here leads to contradiction - Row 4 would end up with more than 2 stars (row 2, column 8).
27. Triple analysis (Row 4 + Region 5 + Row 5): every legal combination of their stars rules these cells out (row 3, column 2).
28. Squeeze (columns 2-3): the band's clumps can only just fit its stars (row 3, column 4).
29. Lookahead: Placing star here leads to contradiction - columns 4-7 must hold 8 stars but the regions there could only supply 7 (row 4, column 6).
30. Lookahead: Placing star here leads to contradiction - row 3 can only hold 2 stars but the regions there would be forced to place 3 (row 3, column 3).
31. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 6, column 1).
32. Three candidates with two adjacent: Isolated candidate must hold a star (row 7, column 4).
33. Mark 3 cells adjacent to stars as X (row 6, column 3).
34. Region completion: 1 star needed, 1 candidate (row 6, column 2).
35. Mark 1 cell adjacent to stars as X (row 5, column 3).
36. Column 2 complete: Mark 1 remaining cell as X (row 1, column 2).
37. Clump analysis (Column 3): candidate clumps can only just supply the remaining stars (row 1, column 4).
38. Column completion: 1 star needed, 1 candidate (row 9, column 4).
39. Mark 1 cell adjacent to stars as X (row 9, column 5).
40. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 2, column 6).
41. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 5).
42. Clump analysis (Column 3): each clump must supply its full share of stars (row 4, column 3).
43. Squeeze (columns 5-6): the band's clumps can only just fit its stars (row 9, column 7).
44. Triple analysis (Row 5 + Region 4 + Region 1): every legal combination of their stars rules these cells out (row 5, column 6).
45. Clump analysis (Region 5): candidate clumps can only just supply the remaining stars (row 2, column 7).
46. Region completion: 1 star needed, 1 candidate (row 1, column 7).
47. Row 1 complete: Mark 3 remaining cells as X (row 1, column 1).
48. Column completion: 1 star needed, 1 candidate (row 2, column 3).
49. Crowding (Region 7): a star here would leave too little room for its 2 remaining stars (row 6, column 9).
50. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 6, column 7).
51. Generalized counting (rows 2-3): region star limits exclude these cells (row 4, column 1).
52. Squeeze (rows 4-5): the band's clumps can only just fit its stars (row 6, column 8).
53. Squeeze (rows 4-6): the band's clumps can only just fit its stars (row 5, column 9).
54. Squeeze (columns 8-9): the band's clumps can only just fit its stars (row 4, column 9).
55. Region completion: 2 stars needed, 2 candidates (row 5, column 8).
56. Region completion: 1 star needed, 1 candidate (row 7, column 8).
57. Mark 3 cells adjacent to stars as X (row 7, column 7).
58. Row completion: 1 star needed, 1 candidate (row 4, column 5).
59. Mark 2 cells adjacent to stars as X (row 3, column 6).
60. Region completion: 1 star needed, 1 candidate (row 6, column 6).
61. Mark 1 cell adjacent to stars as X (row 7, column 6).
62. Row completion: 1 star needed, 1 candidate (row 5, column 10).
63. Mark 1 cell adjacent to stars as X (row 6, column 10).
64. Row 7 complete: Mark 1 remaining cell as X (row 7, column 10).
65. Column completion: 1 star needed, 1 candidate (row 3, column 7).
66. Mark 1 cell adjacent to stars as X (row 3, column 8).
67. Column 8 complete: Mark 1 remaining cell as X (row 10, column 8).
68. Row completion: 1 star needed, 1 candidate (row 10, column 9).
69. Mark 1 cell adjacent to stars as X (row 9, column 10).
70. Region completion: 1 star needed, 1 candidate (row 8, column 10).
71. Row 8 complete: Mark 1 remaining cell as X (row 8, column 6).
72. Region completion: 1 star needed, 1 candidate (row 9, column 6).
73. Column completion: 1 star needed, 1 candidate (row 3, column 9).
74. Mark 2 cells adjacent to stars as X (row 2, column 10).
75. Row completion: 1 star needed, 1 candidate (row 2, column 1).
76. Mark 1 cell adjacent to stars as X (row 3, column 1).
77. Solved! Every row, column, and region has its two stars, none touching.