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