Hard Star Battle answer — October 24, 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 8, 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 8, column 2).
4. Three candidates with two adjacent: Isolated candidate must hold a star (row 7, column 1).
5. Mark 3 cells adjacent to stars as X (row 6, column 1).
6. 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 7).
7. 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 7).
8. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 7, column 3).
9. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 5, column 5).
10. Clump analysis (Region 3): candidate clumps can only just supply the remaining stars (row 5, column 3).
11. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 4, column 1).
12. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 4, column 2).
13. Clump analysis (Region 6): candidate clumps can only just supply the remaining stars (row 2, column 1).
14. Crowding (Row 6): a star here would leave too little room for its 2 remaining stars (row 7, column 7).
15. Squeeze (columns 2-3): the band's clumps can only just fit its stars (row 2, column 3).
16. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 2).
17. Clump analysis (Row 2): candidate clumps can only just supply the remaining stars (row 1, column 6).
18. 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).
19. Clump analysis (Row 4): candidate clumps can only just supply the remaining stars (row 5, column 6).
20. Region completion: 2 stars needed, 2 candidates (row 6, column 6).
21. Mark 1 cell adjacent to stars as X (row 7, column 6).
22. Region completion: 1 star needed, 1 candidate (row 6, column 8).
23. Mark 2 cells adjacent to stars as X (row 7, column 8).
24. Row completion: 1 star needed, 1 candidate (row 5, column 4).
25. Mark 2 cells adjacent to stars as X (row 4, column 5).
26. Row completion: 1 star needed, 1 candidate (row 7, column 4).
27. Mark 1 cell adjacent to stars as X (row 8, column 4).
28. Clump analysis (Row 4): candidate clumps can only just supply the remaining stars (row 3, column 7).
29. Clump analysis (Row 8): candidate clumps can only just supply the remaining stars (row 9, column 6).
30. Three candidates with two adjacent: Isolated candidate must hold a star (row 9, column 3).
31. Mark 1 cell adjacent to stars as X (row 9, column 2).
32. Region completion: 1 star needed, 1 candidate (row 9, column 1).
33. Row 9 complete: Mark 1 remaining cell as X (row 9, column 5).
34. Region completion: 1 star needed, 1 candidate (row 8, column 6).
35. Mark 1 cell adjacent to stars as X (row 8, column 7).
36. Column 1 complete: Mark 2 remaining cells as X (row 1, column 1).
37. Region completion: 1 star needed, 1 candidate (row 3, column 2).
38. Mark 1 cell adjacent to stars as X (row 3, column 3).
39. Row completion: 1 star needed, 1 candidate (row 3, column 5).
40. Mark 3 cells adjacent to stars as X (row 2, column 5).
41. Row completion: 2 stars needed, 2 candidates (row 2, column 7).
42. Mark 1 cell adjacent to stars as X (row 1, column 7).
43. Row completion: 1 star needed, 1 candidate (row 2, column 9).
44. Mark 1 cell adjacent to stars as X (row 1, column 9).
45. Column 2 complete: Mark 1 remaining cell as X (row 1, column 2).
46. Region completion: 1 star needed, 1 candidate (row 1, column 3).
47. Row completion: 1 star needed, 1 candidate (row 1, column 5).
48. Column completion: 1 star needed, 1 candidate (row 4, column 7).
49. Mark 1 cell adjacent to stars as X (row 4, column 8).
50. Row completion: 1 star needed, 1 candidate (row 4, column 9).
51. Column completion: 1 star needed, 1 candidate (row 8, column 8).
52. Mark 1 cell adjacent to stars as X (row 8, column 9).
53. Solved! Every row, column, and region has its two stars, none touching.