Medium Star Battle answer — July 19, 2025

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 7, column 7).
3. Three candidates with two adjacent: Isolated candidate must hold a star (row 7, column 8).
4. Mark 7 cells adjacent to stars as X (row 6, column 7).
5. Two-option rule: Cell adjacent to both candidates (row 7, column 5).
6. Two-option rule: Cell adjacent to both candidates (row 8, column 5).
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 5).
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 8, column 1).
9. Three candidates with two adjacent: Isolated candidate must hold a star (row 7, column 1).
10. Mark 4 cells adjacent to stars as X (row 6, column 1).
11. Row 7 complete: Mark 3 remaining cells as X (row 7, column 3).
12. Region completion: 1 star needed, 1 candidate (row 8, column 6).
13. Mark 3 cells adjacent to stars as X (row 9, column 5).
14. 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 5).
15. Three candidates with two adjacent: Isolated candidate must hold a star (row 6, column 4).
16. Mark 3 cells adjacent to stars as X (row 5, column 3).
17. Row completion: 1 star needed, 1 candidate (row 6, column 6).
18. Mark 2 cells adjacent to stars as X (row 5, column 6).
19. Column 6 complete: Mark 4 remaining cells as X (row 1, column 6).
20. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 2).
21. Mark 4 cells adjacent to stars as X (row 4, column 1).
22. Two-option rule: Cell adjacent to both candidates (row 9, column 3).
23. Two-option rule: Cell adjacent to both candidates (row 9, column 4).
24. 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 8).
25. 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 8).
26. Three candidates with two adjacent: Isolated candidate must hold a star (row 4, column 7).
27. Mark 2 cells adjacent to stars as X (row 3, column 7).
28. Row completion: 1 star needed, 1 candidate (row 5, column 9).
29. Mark 1 cell adjacent to stars as X (row 4, column 9).
30. Region completion: 1 star needed, 1 candidate (row 3, column 9).
31. Mark 2 cells adjacent to stars as X (row 2, column 8).
32. Column 9 complete: Mark 2 remaining cells as X (row 1, column 9).
33. Region completion: 1 star needed, 1 candidate (row 9, column 8).
34. Column 8 complete: Mark 1 remaining cell as X (row 1, column 8).
35. Three candidates with two adjacent: Isolated candidate must hold a star (row 1, column 5).
36. Mark 3 cells adjacent to stars as X (row 1, column 4).
37. Two last candidates (row 4): Eliminate 2 cells adjacent to both (row 3, column 4).
38. Column completion: 1 star needed, 1 candidate (row 4, column 5).
39. Mark 1 cell adjacent to stars as X (row 4, column 4).
40. Column completion: 1 star needed, 1 candidate (row 8, column 4).
41. Mark 1 cell adjacent to stars as X (row 8, column 3).
42. Three candidates in a column: Middle cell can't hold a star (row 2, column 3).
43. Column completion: 2 stars needed, 2 candidates (row 1, column 3).
44. Mark 2 cells adjacent to stars as X (row 1, column 2).
45. Region complete: Mark 1 remaining cell as X (row 1, column 1).
46. Row 1 complete: Mark 1 remaining cell as X (row 1, column 7).
47. Region completion: 1 star needed, 1 candidate (row 2, column 7).
48. Row completion: 1 star needed, 1 candidate (row 2, column 1).
49. Mark 2 cells adjacent to stars as X (row 3, column 1).
50. Region completion: 1 star needed, 1 candidate (row 3, column 3).
51. Column 1 complete: Mark 1 remaining cell as X (row 9, column 1).
52. Region completion: 1 star needed, 1 candidate (row 9, column 2).
53. Solved! Every row, column, and region has its two stars, none touching.