Expert Star Battle answer — May 9, 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 3): candidate clumps can only just supply the remaining stars (row 3, column 8).
3. Clump analysis (Region 5): candidate clumps can only just supply the remaining stars (row 8, column 4).
4. 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 8).
5. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 7, column 7).
6. Composite container (columns 1-6): Regions 2, 4, 7 and 8 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 5).
7. Joint analysis (Column 8 + Column 9): every legal combination of their stars rules these cells out (row 7, column 9).
8. Joint analysis (Region 1 + Column 8): every legal combination of their stars rules these cells out (row 5, column 7).
9. Lookahead: Placing star here leads to contradiction - stars at R6C8 and R6C9 would touch (row 7, column 6).
10. Clump analysis (Row 7): candidate clumps can only just supply the remaining stars (row 6, column 2).
11. Joint analysis (Row 5 + Region 2): every legal combination of their stars rules these cells out (row 4, column 2).
12. Joint analysis (Column 2 + Column 1): every legal combination of their stars rules these cells out (row 2, column 2).
13. Joint analysis (Column 2 + Region 4): every legal combination of their stars rules these cells out (row 4, column 3).
14. Joint analysis (Region 1 + Region 9): every legal combination of their stars rules these cells out (row 9, column 6).
15. 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 3).
16. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 2).
17. Mark 3 cells adjacent to stars as X (row 5, column 1).
18. Clump analysis (Row 5): candidate clumps can only just supply the remaining stars (row 4, column 5).
19. Clump analysis (Row 6): candidate clumps can only just supply the remaining stars (row 5, column 6).
20. Two last candidates (row 5): Eliminate 1 cell adjacent to both (row 4, column 4).
21. Clump analysis (Row 4): candidate clumps can only just supply the remaining stars (row 3, column 6).
22. Clump analysis (Row 3): candidate clumps can only just supply the remaining stars (row 2, column 4).
23. Crowding (Column 6): a star here would leave too little room for its 2 remaining stars (row 5, column 5).
24. Row completion: 1 star needed, 1 candidate (row 5, column 4).
25. Squeeze (rows 2-3): the band's clumps can only just fit its stars (row 1, column 8).
26. Squeeze (rows 8-9): the band's clumps can only just fit its stars (row 9, column 4).
27. Squeeze (rows 8-9): each clump in the band must supply its full share of stars (row 8, column 9).
28. Generalized counting (columns 1-1): region star limits exclude these cells (row 1, column 2).
29. Squeeze (columns 1-2): each clump in the band must supply its full share of stars (row 1, column 1).
30. Composite container (columns 2-8): Regions 1, 2, 4, 5 and 8 are confined here, so the leftover cells owe exactly 5 of the band's 14 stars - a star on these cells would crowd them out (row 7, column 4).
31. Region completion: 1 star needed, 1 candidate (row 4, column 6).
32. Mark 2 cells adjacent to stars as X (row 3, column 5).
33. Three candidates with two adjacent: Isolated candidate must hold a star (row 2, column 7).
34. Mark 4 cells adjacent to stars as X (row 1, column 6).
35. Column completion: 1 star needed, 1 candidate (row 6, column 6).
36. Mark 2 cells adjacent to stars as X (row 6, column 7).
37. Column completion: 2 stars needed, 2 candidates (row 4, column 8).
38. Mark 1 cell adjacent to stars as X (row 4, column 9).
39. Column completion: 1 star needed, 1 candidate (row 6, column 8).
40. Mark 1 cell adjacent to stars as X (row 6, column 9).
41. Region complete: Mark 1 remaining cell as X (row 8, column 7).
42. Region completion: 1 star needed, 1 candidate (row 8, column 5).
43. Mark 1 cell adjacent to stars as X (row 9, column 5).
44. Region completion: 1 star needed, 1 candidate (row 9, column 7).
45. Column completion: 1 star needed, 1 candidate (row 1, column 5).
46. Mark 1 cell adjacent to stars as X (row 1, column 4).
47. Row 1 complete: Mark 1 remaining cell as X (row 1, column 9).
48. Region completion: 1 star needed, 1 candidate (row 2, column 9).
49. Row 2 complete: Mark 1 remaining cell as X (row 2, column 3).
50. Column completion: 1 star needed, 1 candidate (row 3, column 4).
51. Mark 1 cell adjacent to stars as X (row 3, column 3).
52. Region completion: 1 star needed, 1 candidate (row 3, column 2).
53. Mark 1 cell adjacent to stars as X (row 3, column 1).
54. Region completion: 1 star needed, 1 candidate (row 7, column 1).
55. Mark 1 cell adjacent to stars as X (row 7, column 2).
56. Region completion: 1 star needed, 1 candidate (row 7, column 3).
57. Solved! Every row, column, and region has its two stars, none touching.