Expert Star Battle answer — August 27, 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 1).
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 5, column 2).
4. Three candidates with two adjacent: Isolated candidate must hold a star (row 6, column 2).
5. Mark 6 cells adjacent to stars as X (row 5, column 3).
6. Two-option rule: Cell adjacent to both candidates (row 3, column 1).
7. Two-option rule: Cell adjacent to both candidates (row 3, column 2).
8. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 6, column 9).
9. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 2, column 3).
10. Crowding (Region 7): a star here would leave too little room for its 2 remaining stars (row 5, column 4).
11. 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).
12. Lookahead: Placing star here leads to contradiction - Region 7 would only have room for 1 of the 2 stars it still needs (row 4, column 2).
13. Region completion: 1 star needed, 1 candidate (row 4, column 1).
14. Joint analysis (Row 4 + Region 1): every legal combination of their stars rules these cells out (row 4, column 8).
15. Joint analysis (Region 8 + Row 4): every legal combination of their stars rules these cells out (row 4, column 6).
16. Joint analysis (Region 8 + Column 4): every legal combination of their stars rules these cells out (row 6, column 4).
17. Region completion: 2 stars needed, 2 candidates (row 4, column 3).
18. Mark 3 cells adjacent to stars as X (row 3, column 3).
19. Region completion: 1 star needed, 1 candidate (row 8, column 2).
20. Mark 5 cells adjacent to stars as X (row 8, column 1).
21. Region completion: 2 stars needed, 2 candidates (row 2, column 4).
22. Mark 5 cells adjacent to stars as X (row 1, column 3).
23. Region completion: 1 star needed, 1 candidate (row 5, column 5).
24. Mark 3 cells adjacent to stars as X (row 5, column 6).
25. Row 4 complete: Mark 3 remaining cells as X (row 4, column 7).
26. Column 2 complete: Mark 3 remaining cells as X (row 1, column 2).
27. Column completion: 1 star needed, 1 candidate (row 10, column 3).
28. Mark 2 cells adjacent to stars as X (row 9, column 4).
29. Two last candidates (column 4): Eliminate 2 cells adjacent to both (row 7, column 5).
30. Two last candidates (column 5): Eliminate 2 cells adjacent to both (row 9, column 6).
31. Clump analysis (Row 3): candidate clumps can only just supply the remaining stars (row 2, column 7).
32. Clump analysis (Region 9): candidate clumps can only just supply the remaining stars (row 10, column 1).
33. Region completion: 1 star needed, 1 candidate (row 8, column 4).
34. Mark 2 cells adjacent to stars as X (row 7, column 4).
35. Row 8 complete: Mark 5 remaining cells as X (row 8, column 6).
36. Column completion: 1 star needed, 1 candidate (row 10, column 5).
37. Row 10 complete: Mark 4 remaining cells as X (row 10, column 7).
38. Clump analysis (Row 7): candidate clumps can only just supply the remaining stars (row 6, column 7).
39. Three candidates with two adjacent: Isolated candidate must hold a star (row 3, column 6).
40. Mark 1 cell adjacent to stars as X (row 3, column 7).
41. Two-option rule: Cell adjacent to both candidates (row 7, column 7).
42. Two-option rule: Cell adjacent to both candidates (row 7, column 9).
43. Two last candidates (row 6): Eliminate 1 cell adjacent to both (row 5, column 9).
44. Crowding (Column 9): a star here would leave too little room for its 2 remaining stars (row 2, column 8).
45. Row completion: 1 star needed, 1 candidate (row 2, column 1).
46. Mark 1 cell adjacent to stars as X (row 1, column 1).
47. Squeeze (rows 6-7): the band's clumps can only just fit its stars (row 9, column 7).
48. Region completion: 1 star needed, 1 candidate (row 7, column 6).
49. Region completion: 1 star needed, 1 candidate (row 1, column 7).
50. Mark 1 cell adjacent to stars as X (row 1, column 8).
51. Column completion: 1 star needed, 1 candidate (row 5, column 7).
52. Mark 2 cells adjacent to stars as X (row 5, column 8).
53. Region completion: 1 star needed, 1 candidate (row 7, column 8).
54. Row 5 complete: Mark 1 remaining cell as X (row 5, column 10).
55. Region completion: 2 stars needed, 2 candidates (row 3, column 9).
56. Mark 2 cells adjacent to stars as X (row 3, column 8).
57. Region completion: 1 star needed, 1 candidate (row 6, column 10).
58. Mark 1 cell adjacent to stars as X (row 7, column 10).
59. Column completion: 1 star needed, 1 candidate (row 9, column 8).
60. Mark 1 cell adjacent to stars as X (row 9, column 9).
61. Region completion: 1 star needed, 1 candidate (row 9, column 10).
62. Column completion: 1 star needed, 1 candidate (row 1, column 9).
63. Mark 1 cell adjacent to stars as X (row 1, column 10).
64. Solved! Every row, column, and region has its two stars, none touching.