Expert Star Battle answer — October 20, 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 7): candidate clumps can only just supply the remaining stars (row 7, column 9).
3. Clump analysis (Region 9): candidate clumps can only just supply the remaining stars (row 6, column 4).
4. Crowding (Region 10): a star here would leave too little room for its 2 remaining stars (row 3, column 6).
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 5, column 6).
6. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 7).
7. Mark 3 cells adjacent to stars as X (row 4, column 8).
8. Lookahead: Placing star here leads to contradiction - rows 1-3 can only hold 6 stars but the regions there would be forced to place 7 (row 3, column 1).
9. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 7, column 2).
10. Quad analysis (Row 5 + Region 3 + Region 4 + Column 1): every legal combination of their stars rules these cells out (row 5, column 3).
11. Star claim: Region 10 must place a star in row 4; cells touching all its options are eliminated (row 3, column 4).
12. Generalized counting (rows 1-4): region star limits exclude these cells (row 3, column 8).
13. 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 2).
14. Clump analysis (Row 4): candidate clumps can only just supply the remaining stars (row 3, column 2).
15. Region completion: 1 star needed, 1 candidate (row 6, column 5).
16. Mark 3 cells adjacent to stars as X (row 7, column 4).
17. Row completion: 2 stars needed, 2 candidates (row 3, column 7).
18. Mark 3 cells adjacent to stars as X (row 2, column 6).
19. Row completion: 1 star needed, 1 candidate (row 3, column 10).
20. Mark 2 cells adjacent to stars as X (row 2, column 9).
21. Column 7 complete: Mark 5 remaining cells as X (row 1, column 7).
22. 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 5).
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 2, column 5).
24. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 6).
25. Two-option rule: Cell adjacent to both candidates (row 1, column 3).
26. Two-option rule: Cell adjacent to both candidates (row 2, column 3).
27. Clump analysis (Row 2): candidate clumps can only just supply the remaining stars (row 1, column 1).
28. Region completion: 1 star needed, 1 candidate (row 2, column 4).
29. Three candidates with two adjacent: Isolated candidate must hold a star (row 4, column 2).
30. Mark 2 cells adjacent to stars as X (row 4, column 3).
31. Three candidates with two adjacent: Isolated candidate must hold a star (row 6, column 3).
32. Mark 1 cell adjacent to stars as X (row 7, column 3).
33. Row 6 complete: Mark 3 remaining cells as X (row 6, column 1).
34. Region completion: 1 star needed, 1 candidate (row 7, column 1).
35. Mark 2 cells adjacent to stars as X (row 8, column 1).
36. Clump analysis (Column 3): candidate clumps can only just supply the remaining stars (row 9, column 2).
37. Clump analysis (Column 6): candidate clumps can only just supply the remaining stars (row 9, column 5).
38. Clump analysis (Region 7): candidate clumps can only just supply the remaining stars (row 1, column 10).
39. Row completion: 1 star needed, 1 candidate (row 5, column 9).
40. Clump analysis (Region 2): candidate clumps can only just supply the remaining stars (row 9, column 9).
41. Clump analysis (Column 10): each clump must supply its full share of stars (row 10, column 9).
42. Mark 4 cells adjacent to stars as X (row 9, column 8).
43. Region completion: 1 star needed, 1 candidate (row 8, column 8).
44. Mark 1 cell adjacent to stars as X (row 7, column 8).
45. Row completion: 1 star needed, 1 candidate (row 7, column 10).
46. Mark 1 cell adjacent to stars as X (row 8, column 10).
47. Column completion: 1 star needed, 1 candidate (row 1, column 8).
48. Mark 1 cell adjacent to stars as X (row 1, column 9).
49. 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 6).
50. Row completion: 2 stars needed, 2 candidates (row 9, column 1).
51. Mark 2 cells adjacent to stars as X (row 10, column 1).
52. Row completion: 1 star needed, 1 candidate (row 9, column 3).
53. Mark 4 cells adjacent to stars as X (row 8, column 3).
54. Region complete: Mark 1 remaining cell as X (row 8, column 5).
55. Row completion: 1 star needed, 1 candidate (row 8, column 6).
56. Column 1 complete: Mark 1 remaining cell as X (row 2, column 1).
57. Region completion: 1 star needed, 1 candidate (row 2, column 2).
58. Column completion: 1 star needed, 1 candidate (row 4, column 4).
59. Mark 1 cell adjacent to stars as X (row 4, column 5).
60. Column completion: 1 star needed, 1 candidate (row 10, column 5).
61. Mark 1 cell adjacent to stars as X (row 10, column 6).
62. Solved! Every row, column, and region has its two stars, none touching.