Hard Star Battle answer — June 29, 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 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 2, column 2).
4. Three candidates with two adjacent: Isolated candidate must hold a star (row 3, column 2).
5. Mark 6 cells adjacent to stars as X (row 2, column 3).
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 2).
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 9, column 8).
8. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 10, column 8).
9. Three candidates with two adjacent: Isolated candidate must hold a star (row 10, column 9).
10. Mark 3 cells adjacent to stars as X (row 9, column 9).
11. Two-option rule: Cell adjacent to both candidates (row 9, column 6).
12. Two-option rule: Cell adjacent to both candidates (row 10, column 6).
13. Three candidates with two adjacent: Isolated candidate must hold a star (row 9, column 5).
14. Mark 6 cells adjacent to stars as X (row 8, column 4).
15. Region completion: 1 star needed, 1 candidate (row 9, column 3).
16. Mark 5 cells adjacent to stars as X (row 8, column 2).
17. Row 9 complete: Mark 2 remaining cells as X (row 9, column 1).
18. Region completion: 1 star needed, 1 candidate (row 10, column 7).
19. Row 10 complete: Mark 1 remaining cell as X (row 10, column 1).
20. Clump analysis (Region 8): candidate clumps can only just supply the remaining stars (row 6, column 2).
21. Clump analysis (Region 10): candidate clumps can only just supply the remaining stars (row 8, column 8).
22. Squeeze (columns 3-4): the band's clumps can only just fit its stars (row 2, column 5).
23. Composite container (columns 1-6): Regions 1, 3, 4 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 12 stars - a star on these cells would crowd them out (row 1, column 5).
24. Clump analysis (Region 1): candidate clumps can only just supply the remaining stars (row 4, column 5).
25. Crowding (Row 2): a star here would leave too little room for its 2 remaining stars (row 1, column 9).
26. Crowding (Region 3): a star here would leave too little room for its 2 remaining stars (row 6, column 5).
27. Composite container (columns 1-6): Regions 1, 3, 4 and 8 are confined here, so the leftover cells owe exactly 2 of the band's 12 stars - impossible without stars on these cells (row 1, column 6).
28. Clump analysis (Region 4): candidate clumps can only just supply the remaining stars (row 1, column 4).
29. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 3, column 5).
30. Two last candidates (column 5): Eliminate 1 cell adjacent to both (row 6, column 6).
31. Clump analysis (Region 2): candidate clumps can only just supply the remaining stars (row 4, column 6).
32. Three candidates with two adjacent: Isolated candidate must hold a star (row 7, column 8).
33. Mark 4 cells adjacent to stars as X (row 6, column 8).
34. Row completion: 2 stars needed, 2 candidates (row 8, column 1).
35. Mark 2 cells adjacent to stars as X (row 7, column 1).
36. Row completion: 1 star needed, 1 candidate (row 8, column 10).
37. Mark 1 cell adjacent to stars as X (row 7, column 10).
38. Region completion: 1 star needed, 1 candidate (row 5, column 8).
39. Mark 4 cells adjacent to stars as X (row 4, column 7).
40. Region completion: 1 star needed, 1 candidate (row 3, column 7).
41. Mark 3 cells adjacent to stars as X (row 2, column 8).
42. Row 3 complete: Mark 2 remaining cells as X (row 3, column 4).
43. Region completion: 2 stars needed, 2 candidates (row 2, column 4).
44. Region completion: 1 star needed, 1 candidate (row 4, column 4).
45. Mark 2 cells adjacent to stars as X (row 5, column 3).
46. Row completion: 1 star needed, 1 candidate (row 4, column 10).
47. Mark 1 cell adjacent to stars as X (row 5, column 10).
48. Column completion: 1 star needed, 1 candidate (row 1, column 2).
49. Mark 1 cell adjacent to stars as X (row 1, column 1).
50. Column completion: 1 star needed, 1 candidate (row 6, column 3).
51. Mark 1 cell adjacent to stars as X (row 7, column 4).
52. Region completion: 1 star needed, 1 candidate (row 5, column 6).
53. Row 5 complete: Mark 1 remaining cell as X (row 5, column 1).
54. Region completion: 1 star needed, 1 candidate (row 6, column 1).
55. Row 6 complete: Mark 1 remaining cell as X (row 6, column 10).
56. Column completion: 1 star needed, 1 candidate (row 7, column 5).
57. Mark 1 cell adjacent to stars as X (row 7, column 6).
58. Column completion: 1 star needed, 1 candidate (row 2, column 9).
59. Mark 1 cell adjacent to stars as X (row 2, column 10).
60. Solved! Every row, column, and region has its two stars, none touching.